Saturday quiz – May 19, 2012 – answers and discussion

Here are the answers with discussion for yesterday’s quiz. The information provided should help you understand the reasoning behind the answers. If you haven’t already done the Quiz from yesterday then have a go at it before you read the answers. I hope this helps you develop an understanding of Modern Monetary Theory (MMT) and its application to macroeconomic thinking. Comments as usual welcome, especially if I have made an error.

Question 1:

Real wages in Greece rose during the Euro period leading up to the crisis because the rate of growth in earnings outstripped its low labour productivity growth.

The answer is False.

The question requires you to understand what determines the real wage and what the relationship between earnings and labour productivity growth is. When economists do not specify the unit you should always assume they are talking in nominal terms. So the reference to the “rate of growth of earnings” is in terms of the monetary unit which is the common understanding that people would have of the term.

In terms of the logic of the question, that would also be the only sensible interpretation.

The real wage is defined as the purchasing power equivalent on the nominal wage that workers get paid each period. To compute the real wage we need to consider two variables: (a) the nominal wage (W) and the aggregate price level (P).

We might consider the aggregate price level to be measured by the consumer price index (CPI) although there are huge debates about that. But in a sense, this macroeconomic price level doesn’t exist but represents some abstract measure of the general movement in all prices in the economy.

Macroeconomics is hard to learn because it involves these abstract variables that are never observed – like the price level, like “the interest rate” etc. They are just stylisations of the general tendency of all the different prices and interest rates.

Now the nominal wage (W) – that is paid by employers to workers is determined in the labour market – by the contract of employment between the worker and the employer. The price level (P) is determined in the goods market – by the interaction of total supply of output and aggregate demand for that output although there are complex models of firm price setting that use cost-plus mark-up formulas with demand just determining volume sold. We shouldn’t get into those debates here.

The inflation rate is just the continuous growth in the price level (P). A once-off adjustment in the price level is not considered by economists to constitute inflation.

So the real wage (w) tells us what volume of real goods and services the nominal wage (W) will be able to command and is obviously influenced by the level of W and the price level. For a given W, the lower is P the greater the purchasing power of the nominal wage and so the higher is the real wage (w).

We write the real wage (w) as W/P. So if W = 10 and P = 1, then the real wage (w) = 10 meaning that the current wage will buy 10 units of real output. If P rose to 2 then w = 5, meaning the real wage was now cut by one-half.

The relationship between the real wage and labour productivity relates to movements in the unit costs, real unit labour costs and the wage and profit shares in national income.

The wage share in nominal GDP is expressed as the total wage bill as a percentage of nominal GDP. Economists differentiate between nominal GDP ($GDP), which is total output produced at market prices and real GDP (GDP), which is the actual physical equivalent of the nominal GDP. We will come back to that distinction soon.

To compute the wage share we need to consider total labour costs in production and the flow of production ($GDP) each period.

Employment (L) is a stock and is measured in persons (averaged over some period like a month or a quarter or a year.

The wage bill is a flow and is the product of total employment (L) and the average wage (w) prevailing at any point in time. Stocks (L) become flows if it is multiplied by a flow variable (W). So the wage bill is the total labour costs in production per period.

So the wage bill = W.L

The wage share is just the total labour costs expressed as a proportion of $GDP – (W.L)/$GDP in nominal terms, usually expressed as a percentage. We can actually break this down further.

Labour productivity (LP) is the units of real GDP per person employed per period. Using the symbols already defined this can be written as:

LP = GDP/L

so it tells us what real output (GDP) each labour unit that is added to production produces on average.

Nominal GDP ($GDP) can be written as P.GDP, where the P values the real physical output.

Now if you put of these concepts together you get an interesting framework. To help you follow the logic here are the terms developed and be careful not to confuse $GDP (nominal) with GDP (real):

• Wage share = (W.L)/$GDP
• Nominal GDP: $GDP = P.GDP
• Labour productivity: LP = GDP/L
• Real wage: w = W/P

By substituting the expression for Nominal GDP into the wage share measure we get:

Wage share = (W.L)/P.GDP

In this area of economics, we often look for alternative way to write this expression – it maintains the equivalence (that is, obeys all the rules of algebra) but presents the expression (in this case the wage share) in a different “view”.

So we can write as an equivalent:

Wage share – (W/P).(L/GDP)

Now if you note that (L/GDP) is the inverse (reciprocal) of the labour productivity term (GDP/L). We can use another rule of algebra (reversing the invert and multiply rule) to rewrite this expression again in a more interpretable fashion.

So an equivalent but more convenient measure of the wage share is:

Wage share = (W/P)/(GDP/L) – that is, the real wage (W/P) divided by labour productivity (GDP/L).

I won’t show this but I could also express this in growth terms such that if the growth in the real wage equals labour productivity growth the wage share is constant. The algebra is simple but we have done enough of that already.

That journey might have seemed difficult to non-economists (or those not well-versed in algebra) but it produces a very easy to understand formula for the wage share.

Two other points to note. The wage share is also equivalent to the real unit labour cost (RULC) measures that Treasuries and central banks use to describe trends in costs within the economy. Please read my blog – Saturday Quiz – May 15, 2010 – answers and discussion – for more discussion on this point.

Now it becomes obvious that if the nominal wage (W) and the price level (P) are growing at the pace the real wage is constant. And if the real wage is growing at the same rate as labour productivity, then both terms in the wage share ratio are equal and so the wage share is constant.

The wage share was constant for a long time during the Post Second World period and this constancy was so marked that Kaldor (the Cambridge economist) termed it one of the great “stylised” facts. So real wages grew in line with productivity growth which was the source of increasing living standards for workers.

The productivity growth provided the “room” in the distribution system for workers to enjoy a greater command over real production and thus higher living standards without threatening inflation.

Since the mid-1980s, the neo-liberal assault on workers’ rights (trade union attacks; deregulation; privatisation; persistently high unemployment) has seen this nexus between real wages and labour productivity growth broken. So while real wages have been stagnant or growing modestly, this growth has been dwarfed by labour productivity growth.

The following blogs may be of further interest to you:

• The origins of the economic crisis
• The fiscal stimulus worked but was captured by profits

Question 2:

Quantitative easing aims to stimulate aggregate demand by reducing long-term investment rates whereas deficit spending aims to stimulate aggregate demand via tax cuts or direct public spending. Both policies ultimately work by increasing the net financial assets held by the non-government sector.

The answer is False.

Quantitative easing involves the central bank buying assets from the private sector – government bonds and high quality corporate debt. So what the central bank is doing is swapping financial assets with the banks – they sell their financial assets and receive back in return extra reserves.

So the central bank is buying one type of financial asset (private holdings of bonds, company paper) and exchanging it for another (reserve balances at the central bank).

The net financial assets in the private sector are in fact unchanged although the portfolio composition of those assets is altered (maturity substitution) which changes yields and returns.

In terms of changing portfolio compositions, quantitative easing increases central bank demand for “long maturity” assets held in the private sector which reduces interest rates at the longer end of the yield curve. These are traditionally thought of as the investment rates. This might increase aggregate demand given the cost of investment funds is likely to drop.

But on the other hand, the lower rates reduce the interest-income of savers who will reduce consumption (demand) accordingly.

How these opposing effects balance out is unclear but the evidence suggests there is not very much impact at all.

Fiscal policy adds net financial assets to the non-government sector by way of contradistinction to quantitative easing.

The following blogs may be of further interest to you:

• Money multiplier and other myths
• Islands in the sun
• Operation twist – then and now
• Quantitative easing 101
• Building bank reserves will not expand credit
• Building bank reserves is not inflationary
• Deficit spending 101 – Part 1
• Deficit spending 101 – Part 2
• Deficit spending 101 – Part 3

Question 3:

In last week’s 2012-13 Budget, the Australian government indicated that it aimed to achieve a budget surplus of 0.1 per cent of GDP in the next financial year. The aim underpins a massive fiscal shift from a budget deficit of around 3 per cent of GDP in 2011-12. If the actual budget outcome remains in deficit at the end of the next financial year the Australian government will be rightly considered not to have gone hard enough on its fiscal austerity plans.

The answer is False.

The actual budget deficit outcome that is reported in the press and by Treasury departments is not a pure measure of the fiscal policy stance adopted by the government at any point in time. As a result, a straightforward interpretation of movements in the actual outcome is difficult.

Economists conceptualise the actual budget outcome as being the sum of two components: (a) a discretionary component – that is, the actual fiscal stance intended by the government; and (b) a cyclical component reflecting the sensitivity of certain fiscal items (tax revenue based on activity and welfare payments to name the most sensitive) to changes in the level of activity.

The former component is now called the “structural deficit” and the latter component is sometimes referred to as the automatic stabilisers.

The structural deficit thus conceptually reflects the chosen (discretionary) fiscal stance of the government independent of cyclical factors.

The cyclical factors refer to the automatic stabilisers which operate in a counter-cyclical fashion. When economic growth is strong, tax revenue improves given it is typically tied to income generation in some way. Further, most governments provide transfer payment relief to workers (unemployment benefits) and this decreases during growth.

In times of economic decline, the automatic stabilisers work in the opposite direction and push the budget balance towards deficit, into deficit, or into a larger deficit. These automatic movements in aggregate demand play an important counter-cyclical attenuating role. So when GDP is declining due to falling aggregate demand, the automatic stabilisers work to add demand (falling taxes and rising welfare payments). When GDP growth is rising, the automatic stabilisers start to pull demand back as the economy adjusts (rising taxes and falling welfare payments).

The problem is then how to determine whether the chosen discretionary fiscal stance is adding to demand (expansionary) or reducing demand (contractionary). It is a problem because a government could be run a contractionary policy by choice but the automatic stabilisers are so strong that the budget goes into deficit which might lead people to think the “government” is expanding the economy.

So just because the budget goes into deficit doesn’t allow us to conclude that the Government has suddenly become of an expansionary mind. In other words, the presence of automatic stabilisers make it hard to discern whether the fiscal policy stance (chosen by the government) is contractionary or expansionary at any particular point in time.

To overcome this ambiguity, economists decided to measure the automatic stabiliser impact against some benchmark or “full capacity” or potential level of output, so that we can decompose the budget balance into that component which is due to specific discretionary fiscal policy choices made by the government and that which arises because the cycle takes the economy away from the potential level of output.

As a result, economists devised what used to be called the Full Employment or High Employment Budget. In more recent times, this concept is now called the Structural Balance. As I have noted in previous blogs, the change in nomenclature here is very telling because it occurred over the period that neo-liberal governments began to abandon their commitments to maintaining full employment and instead decided to use unemployment as a policy tool to discipline inflation.

The Full Employment Budget Balance was a hypothetical construction of the budget balance that would be realised if the economy was operating at potential or full employment. In other words, calibrating the budget position (and the underlying budget parameters) against some fixed point (full capacity) eliminated the cyclical component – the swings in activity around full employment.

This framework allowed economists to decompose the actual budget balance into (in modern terminology) the structural (discretionary) and cyclical budget balances with these unseen budget components being adjusted to what they would be at the potential or full capacity level of output.

The difference between the actual budget outcome and the structural component is then considered to be the cyclical budget outcome and it arises because the economy is deviating from its potential.

So if the economy is operating below capacity then tax revenue would be below its potential level and welfare spending would be above. In other words, the budget balance would be smaller at potential output relative to its current value if the economy was operating below full capacity. The adjustments would work in reverse should the economy be operating above full capacity.

If the budget is in deficit when computed at the “full employment” or potential output level, then we call this a structural deficit and it means that the overall impact of discretionary fiscal policy is expansionary irrespective of what the actual budget outcome is presently. If it is in surplus, then we have a structural surplus and it means that the overall impact of discretionary fiscal policy is contractionary irrespective of what the actual budget outcome is presently.

So you could have a downturn which drives the budget into a deficit but the underlying structural position could be contractionary (that is, a surplus). And vice versa.

The question then relates to how the “potential” or benchmark level of output is to be measured. The calculation of the structural deficit spawned a bit of an industry among the profession raising lots of complex issues relating to adjustments for inflation, terms of trade effects, changes in interest rates and more.

Much of the debate centred on how to compute the unobserved full employment point in the economy. There were a plethora of methods used in the period of true full employment in the 1960s.

As the neo-liberal resurgence gained traction in the 1970s and beyond and governments abandoned their commitment to full employment , the concept of the Non-Accelerating Inflation Rate of Unemployment (the NAIRU) entered the debate – see my blogs – The dreaded NAIRU is still about and Redefing full employment … again!.

The NAIRU became a central plank in the front-line attack on the use of discretionary fiscal policy by governments. It was argued, erroneously, that full employment did not mean the state where there were enough jobs to satisfy the preferences of the available workforce. Instead full employment occurred when the unemployment rate was at the level where inflation was stable.

The estimated NAIRU (it is not observed) became the standard measure of full capacity utilisation. If the economy is running an unemployment equal to the estimated NAIRU then mainstream economists concluded that the economy is at full capacity. Of-course, they kept changing their estimates of the NAIRU which were in turn accompanied by huge standard errors. These error bands in the estimates meant their calculated NAIRUs might vary between 3 and 13 per cent in some studies which made the concept useless for policy purposes.

Typically, the NAIRU estimates are much higher than any acceptable level of full employment and therefore full capacity. The change of the the name from Full Employment Budget Balance to Structural Balance was to avoid the connotations of the past where full capacity arose when there were enough jobs for all those who wanted to work at the current wage levels.

Now you will only read about structural balances which are benchmarked using the NAIRU or some derivation of it – which is, in turn, estimated using very spurious models. This allows them to compute the tax and spending that would occur at this so-called full employment point. But it severely underestimates the tax revenue and overestimates the spending because typically the estimated NAIRU always exceeds a reasonable (non-neo-liberal) definition of full employment.

So the estimates of structural deficits provided by all the international agencies and treasuries etc all conclude that the structural balance is more in deficit (less in surplus) than it actually is – that is, bias the representation of fiscal expansion upwards.

As a result, they systematically understate the degree of discretionary contraction coming from fiscal policy.

The only qualification is if the NAIRU measurement actually represented full employment. Then this source of bias would disappear.

So the fact that the budget deficit is rising might actually indicate that the fiscal austerity program is more contractionary that the Government initially estimated and the automatic stabilisers (loss of tax revenue etc) are more than offsetting the discretionary cuts in net public spending.

The following blogs may be of further interest to you:

• A modern monetary theory lullaby
• Saturday Quiz – April 24, 2010 – answers and discussion
• The dreaded NAIRU is still about!
• Structural deficits – the great con job!
• Structural deficits and automatic stabilisers
• Another economics department to close

Question 4:

Modern Monetary Theory (MMT) brings an understanding of the way central banks purchase and sell government bonds to manage liquidity in the overnight cash markets and thus sustain their target rate of interest. MMT also leads to the conclusion that a central bank could still increase interest rates even if the US government instructed it to directly purchase treasury debt to facilitate the national government’s budget deficit.

The answer is True.

The question hinges on an unstated condition which relates to whether the central bank is offering a support rate on overnight reserves held with it by the private banks.

So what is the explanation?

The central bank conducts what are called liquidity management operations for two reasons. First, it has to ensure that all private cheques (that are funded) clear and other interbank transactions occur smoothly as part of its role of maintaining financial stability. Second, it must maintain aggregate bank reserves at a level that is consistent with its target policy setting given the relationship between the two.

So operating factors link the level of reserves to the monetary policy setting under certain circumstances. These circumstances require that the return on “excess” reserves held by the banks is below the monetary policy target rate. In addition to setting a lending rate (discount rate), the central bank also sets a support rate which is paid on commercial bank reserves held by the central bank.

Commercial banks maintain accounts with the central bank which permit reserves to be managed and also the clearing system to operate smoothly. In addition to setting a lending rate (discount rate), the central bank also can set a support rate which is paid on commercial bank reserves held by the central bank (which might be zero).

Many countries (such as Australia, Canada and zones such as the European Monetary Union) maintain a default return on surplus reserve accounts (for example, the Reserve Bank of Australia pays a default return equal to 25 basis points less than the overnight rate on surplus Exchange Settlement accounts). Other countries like Japan and the US have typically not offered a return on reserves until the onset of the current crisis.

If the support rate is zero then persistent excess liquidity in the cash system (excess reserves) will instigate dynamic forces which would drive the short-term interest rate to zero unless the government sells bonds (or raises taxes). This support rate becomes the interest-rate floor for the economy.

The short-run or operational target interest rate, which represents the current monetary policy stance, is set by the central bank between the discount and support rate. This effectively creates a corridor or a spread within which the short-term interest rates can fluctuate with liquidity variability. It is this spread that the central bank manages in its daily operations.

In most nations, commercial banks by law have to maintain positive reserve balances at the central bank, accumulated over some specified period. At the end of each day commercial banks have to appraise the status of their reserve accounts. Those that are in deficit can borrow the required funds from the central bank at the discount rate.

Alternatively banks with excess reserves are faced with earning the support rate which is below the current market rate of interest on overnight funds if they do nothing. Clearly it is profitable for banks with excess funds to lend to banks with deficits at market rates. Competition between banks with excess reserves for custom puts downward pressure on the short-term interest rate (overnight funds rate) and depending on the state of overall liquidity may drive the interbank rate down below the operational target interest rate. When the system is in surplus overall this competition would drive the rate down to the support rate.

The main instrument of this liquidity management is through open market operations, that is, buying and selling government debt. When the competitive pressures in the overnight funds market drives the interbank rate below the desired target rate, the central bank drains liquidity by selling government debt. This open market intervention therefore will result in a higher value for the overnight rate. Importantly, we characterise the debt-issuance as a monetary policy operation designed to provide interest-rate maintenance. This is in stark contrast to orthodox theory which asserts that debt-issuance is an aspect of fiscal policy and is required to finance deficit spending.

So the fundamental principles that arise in a fiat monetary system which are relevant here are as follows.

• The central bank sets the short-term interest rate based on its policy aspirations.
• Government spending is independent of borrowing which the latter best thought of as coming after spending.
• Government spending provides the net financial assets (bank reserves) which ultimately represent the funds used by the non-government agents to purchase the debt.
• Budget deficits put downward pressure on interest rates contrary to the myths that appear in macroeconomic textbooks about ‘crowding out’.
• The “penalty for not borrowing” is that the interest rate will fall to the bottom of the “corridor” prevailing in the country which may be zero if the central bank does not offer a return on reserves.
• Government debt-issuance is a “monetary policy” operation rather than being intrinsic to fiscal policy, although in a modern monetary paradigm the distinctions between monetary and fiscal policy as traditionally defined are moot.

Accordingly, debt is issued as an interest-maintenance strategy by the central bank. It has no correspondence with any need to fund government spending. Debt might also be issued if the government wants the private sector to have less purchasing power.

Further, the idea that governments would simply get the central bank to “monetise” treasury debt (which is seen orthodox economists as the alternative “financing” method for government spending) is highly misleading. Debt monetisation is usually referred to as a process whereby the central bank buys government bonds directly from the treasury.

In other words, the federal government borrows money from the central bank rather than the public. Debt monetisation is the process usually implied when a government is said to be printing money. Debt monetisation, all else equal, is said to increase the money supply and can lead to severe inflation.

However, as long as the central bank has a mandate to maintain a target short-term interest rate, the size of its purchases and sales of government debt are not discretionary unless it is prepared to offer a support rate to the banks for excess reserves held. In the absence of that offer, once the central bank sets a short-term interest rate target, its portfolio of government securities changes only because of the transactions that are required to support the target interest rate.

The central bank’s lack of control over the quantity of reserves underscores the impossibility of debt monetisation under these circumstances (no support rate). The central bank is unable to monetise the federal debt by purchasing government securities at will because to do so would cause the short-term target rate to fall to zero or to the support rate. If the central bank purchased securities directly from the treasury and the treasury then spent the money, its expenditures would be excess reserves in the banking system. The central bank would be forced to sell an equal amount of securities to support the target interest rate.

The central bank would act only as an intermediary. The central bank would be buying securities from the treasury and selling them to the public. No monetisation would occur.

However, the central bank may agree to pay the short-term interest rate to banks who hold excess overnight reserves. This would eliminate the need by the commercial banks to access the interbank market to get rid of any excess reserves and would allow the central bank to maintain its target interest rate without issuing debt.

The following blogs may be of further interest to you:

• The consolidated government – treasury and central bank
• Saturday Quiz – May 1, 2010 – answers and discussion
• Understanding central bank operations
• Building bank reserves will not expand credit
• Building bank reserves is not inflationary
• Deficit spending 101 – Part 1
• Deficit spending 101 – Part 2
• Deficit spending 101 – Part 3

Question 5 – Premium question

In Year 1, the economy plunges into recession with nominal GDP growth falling to minus -1.0 per cent. The outstanding public debt is equal to the value of the nominal GDP and the nominal interest rate is equal to 1 per cent (and this is the rate the government pays on all outstanding debt). The inflation rate is stable at 1 per cent per annum. The government’s primary budget balance records a deficit equivalent to 1 per cent of GDP and the public debt ratio rises by 3 per cent. In Year 2, the government pushes the primary budget deficit out to 2 per cent of GDP and in doing so stimulates aggregate demand and the economy records a 4 per cent nominal GDP growth rate. All other parameters are unchanged in Year 2. Under these circumstances, the public debt ratio will rise but by an amount less than the rise in the budget deficit because of the real growth in the economy.

The answer is False.

The question relates to the key parameters and relationships that determine the dynamics of the public debt ratio. An understanding of these relationships allows you to debunk statements that are made by those who think fiscal austerity will allow a government to reduce its public debt ratio.

While Modern Monetary Theory (MMT) places no particular importance in the public debt to GDP ratio for a sovereign government, given that insolvency is not an issue, the mainstream debate is dominated by the concept.

The unnecessary practice of fiat currency-issuing governments of issuing public debt $-for-$ to match public net spending (deficits) ensures that the debt levels will rise when there are deficits.

Rising deficits usually mean declining economic activity (especially if there is no evidence of accelerating inflation) which suggests that the debt/GDP ratio may be rising because the denominator is also likely to be falling or rising below trend.

Further, historical experience tells us that when economic growth resumes after a major recession, during which the public debt ratio can rise sharply, the latter always declines again.

It is this endogenous nature of the ratio that suggests it is far more important to focus on the underlying economic problems which the public debt ratio just mirrors.

The mainstream framework begins with the flawed analogy between the household and the sovereign government such that any excess in government spending over taxation receipts has to be “financed” in two ways: (a) by borrowing from the public; and/or (b) by “printing money”.

Neither characterisation is operationally necessary in a fiat monetary system.

The basic analogy is flawed at its most elemental level. The household must work out the financing before it can spend. The household cannot spend first. The government can spend first and ultimately does not have to worry about financing such expenditure.

However, in the mainstream framework for analysing these so-called “financing” choices the government budget constraint (GBC) is the central organising idea. The GBC says that the budget deficit in year t is equal to the change in government debt over year t plus the change in high powered money over year t. So in mathematical terms it is written as:

which you can read in English as saying that Budget deficit = Government spending + Government interest payments – Tax receipts must equal (be “financed” by) a change in Bonds (B) and/or a change in high powered money (H). The triangle sign (delta) is just shorthand for the change in a variable.

However, this is merely an accounting statement. In a stock-flow consistent macroeconomics, this statement will always hold. That is, it has to be true if all the transactions between the government and non-government sector have been corrected added and subtracted.

So in terms of MMT, the previous equation is just an ex post accounting identity that has to be true by definition and has not real economic importance.

But for the mainstream economist, the equation represents an ex ante (before the fact) financial constraint that the government is bound by. The difference between these two conceptions is very significant and the second (mainstream) interpretation cannot be correct if governments issue fiat currency (unless they place voluntary constraints on themselves to act as if it is).

Further, in mainstream economics, money creation is erroneously depicted as the government asking the central bank to buy treasury bonds which the central bank in return then prints money. The government then spends this money.

This is called debt monetisation and you can find out why this is typically not a viable option for a central bank by reading the Deficits 101 suite – Deficit spending 101 – Part 1 – Deficit spending 101 – Part 2 – Deficit spending 101 – Part 3.

Anyway, the mainstream claims that if governments increase the money growth rate (they erroneously call this “printing money”) the extra spending will cause accelerating inflation because there will be “too much money chasing too few goods”! Of-course, we know that proposition to be generally preposterous because economies that are constrained by deficient demand (defined as demand below the full employment level) respond to nominal demand increases by expanding real output rather than prices. There is an extensive literature pointing to this result.

So when governments are expanding deficits to offset a collapse in private spending, there is plenty of spare capacity available to ensure output rather than inflation increases.

But the mainstream claim that because inflation is inevitable if “printing money” occurs, it is unwise to use this option to “finance” net public spending.

Hence they say as a better (but still poor) solution, governments should use debt issuance to “finance” their deficits. Thy also claim this is a poor option because in the short-term it is alleged to increase interest rates and in the longer-term is results in higher future tax rates because the debt has to be “paid back”.

Neither proposition bears scrutiny – you can read these blogs – Will we really pay higher taxes? and Will we really pay higher interest rates? – for further discussion on these points.

The mainstream textbooks are full of elaborate models of debt pay-back, debt stabilisation etc which all claim (falsely) to “prove” that the legacy of past deficits is higher debt and to stabilise the debt, the government must eliminate the deficit which means it must then run a primary surplus equal to interest payments on the existing debt.

A primary budget balance is the difference between government spending (excluding interest rate servicing) and taxation revenue.

The standard mainstream framework, which even the so-called progressives (deficit-doves) use, focuses on the ratio of debt to GDP rather than the level of debt per se. The following equation captures the approach:

So the change in the debt ratio is the sum of two terms on the right-hand side: (a) the difference between the real interest rate (r) and the real GDP growth rate (g) times the initial debt ratio; and (b) the ratio of the primary deficit (G-T) to GDP.

The real interest rate is the difference between the nominal interest rate and the inflation rate. Real GDP is the nominal GDP deflated by the inflation rate. So the real GDP growth rate is equal to the Nominal GDP growth minus the inflation rate.

This standard mainstream framework is used to highlight the dangers of running deficits. But even progressives (not me) use it in a perverse way to justify deficits in a downturn balanced by surpluses in the upturn.

Many mainstream economists and a fair number of so-called progressive economists say that governments should as some point in the business cycle run primary surpluses (taxation revenue in excess of non-interest government spending) to start reducing the debt ratio back to “safe” territory.

Almost all the media commentators that you read on this topic take it for granted that the only way to reduce the public debt ratio is to run primary surpluses.

MMT does not tell us that a currency-issuing government running a deficit can never reduce the debt ratio. The standard formula above can easily demonstrate that a nation running a primary deficit can reduce its public debt ratio over time.

Furthermore, depending on contributions from the external sector, a nation running a deficit will more likely create the conditions for a reduction in the public debt ratio than a nation that introduces an austerity plan aimed at running primary surpluses.

So the real interest rate in our example is 0 (nominal interest rate = 1 minus inflation rate =1) which then leads to the conclusion that that the proposition presented is false.

A growing economy can absorb more debt and keep the debt ratio constant or falling. From the formula above, if the primary budget balance is zero, public debt increases at a rate r but the public debt ratio increases at r – g.

The following Table simulates the two years in question. To make matters simple, assume a public debt ratio at the start of the Year 1 of 100 per cent (so B/Y(-1) = 1) which is equivalent to the statement that “outstanding public debt is equal to the value of the nominal GDP”.

Also the nominal interest rate is 1 per cent and the inflation rate is 1 per cent then the current real interest rate (r) is 0 per cent.

If the nominal GDP is growing at -1 per cent and there is an inflation rate of 1 per cent then real GDP is growing (g) at minus 2 per cent.

Under these conditions, the primary budget surplus would have to be equal to 2 per cent of GDP to stabilise the debt ratio (check it for yourself). So, the question suggests the primary budget deficit is actually 1 per cent of GDP we know by computation that the public debt ratio rises by 3 per cent.

The calculation (using the formula in the Table) is:

Change in B/Y = (0 – (-2))*1 + 1 = 3 per cent.

The data in Year 2 is given in the last column in the Table below. Note the public debt ratio has risen to 1.03 because of the rise from last year. You are told that the budget deficit doubles as per cent of GDP (to 2 per cent) and nominal GDP growth shoots up to 4 per cent which means real GDP growth (given the inflation rate) is equal to 3 per cent.

The corresponding calculation for the change in the public debt ratio is:

Change in B/Y = (0 – 3)*1.03 + 2 = -1.1 per cent.

So the growth in the economy is strong enough to reduce the public debt ratio even though the primary budget deficit has doubled.

It is a highly stylised example truncated into a two-period adjustment to demonstrate the point. In the real world, if the budget deficit is a large percentage of GDP then it might take some years to start reducing the public debt ratio as GDP growth ensures.

So even with an increasing (or unchanged) deficit, real GDP growth can reduce the public debt ratio, which is what has happened many times in past history following economic slowdowns.

Stimulating real growth (that is, in Y) is the most constructive way of reducing the public debt ratio when there is unemployment.

But the best way to reduce the public debt ratio is to stop issuing debt. A sovereign government doesn’t have to issue debt if the central bank is happy to keep its target interest rate at zero or pay interest on excess reserves.

The discussion also demonstrates why tightening monetary policy makes it harder for the government to reduce the public debt ratio – which, of-course, is one of the more subtle mainstream ways to force the government to run surpluses.