Tag: supply-side economics

In her bid to become Conservative party leader, Liz Truss promised to make achieving faster economic growth her number-one policy objective. This would involve pursuing market-orientated supply-side policies.

These policies would include lower taxes on individuals to encourage people to work harder and more efficiently, and lower taxes on business to encourage investment. The policy would also involve deregulation, which would again encourage investment, both domestic and inward investment from overseas. These proposals echoed the policies pursued in the 1980s by President Ronald Reagan in the USA and Margaret Thatcher in the UK.

On September 23, the new Chancellor, Kwasi Kwarteng, presented a ‘mini-Budget’ – although the size of the changes made it far from ‘mini’. This, as anticipated, included policies intended to boost growth, including scrapping the 45% top rate of income tax, which is currently paid by people earning over £150 000 (a policy withdrawn on 3 October after massive objections), cutting the basic rate of income tax from 20% to 19%, scrapping the planned rise in corporation tax from 19% to 25%, scrapping the planned rise in national insurance by 1.25 percentage points, a cut in the stamp duty on house purchase and scrapping the limit placed on bankers’ bonuses. In addition, he announced the introduction of an unlimited number of ‘investment zones’ which would have lower business taxes, streamlined planning rules and lower regulation. The policies would be funded largely from extra government borrowing.

Theoretically, the argument is simple. If people do work harder and firms do invest more, then potential GDP will rise – a rise in aggregate supply. This can be shown on an aggregate demand and supply diagram. If the policy works, the aggregate supply curve will shift to the right. Real GDP will rise and there will be downward pressure on prices. In Figure 1, real GDP will rise from Y₀ to Y₁ and the price level will fall from P₀ to P₁. However, things are not as simple as this. Indeed, there are two major problems.

The first concerns whether tax cuts will incentivise people to work harder. The second concerns what happens to aggregate demand. I addition to this, the policies are likely to have a profound effect on income distribution.

Tax cuts and incentives

Cutting the top rate of income tax would have immediately given people at the top of the income scale a rise in post-tax income. This would have created a substitution effect and an income effect. Each extra pound that such people earn would be worth more in post-tax income – 60p rather than 55p. This would provide an incentive for people to substitute work for leisure as work is now more rewarding. This is the substitution effect. On the other hand, with the windfall of extra income, they now would have needed to work less in order to maintain their post-tax income at its previous level. They may well indeed, therefore, have decided to work less and enjoy more leisure. This is the income effect.

With the diminishing marginal utility of income, generally the richer people are, the bigger will be the income effect and the smaller the substitution effect. Thus, cutting the top rate of income tax may well have led to richer people working less. There is no evidence that the substitution effect would be bigger.

If top rates of income tax are already at a very high level, then cutting then may well encourage more work. After all, there is little incentive to work more if the current rate of tax is over 90%, say. Cutting them to 80% could have a big effect. This was the point made by Art Laffer, one of Ronald Reagan’s advisors. He presented his arguments in terms of the now famous ‘Laffer curve’, shown in Figure 2. This shows the total tax revenue raised at different tax rates.

If the average tax rate were zero, no revenue would be raised. As the tax rate is raised above zero, tax revenues will increase. The curve will be upward sloping. Eventually, however, the curve will peak (at tax rate t₁). Thereafter, tax rates become so high that the resulting fall in output more than offsets the rise in tax rate. When the tax rate reaches 100 per cent, the revenue will once more fall to zero, since no one will bother to work.

If the economy were currently to the right of t₁, then cutting taxes would increase revenue as there would be a major substitution effect. However, most commentators argue that the UK economy is to the left of t₁ and that cutting the top rate would reduce tax revenues. Analysis by the Office for Budget Responsibility in 2012 suggested that t₁ for the top rate of income tax was at around 48% and that cutting the rate below that would reduce tax revenue. Clearly according to this analysis, 40% is considerably below t₁.

As far as corporation tax is concerned, the 19% rate is the lowest in the G20 and yet the UK suffers from low rates of both domestic investment and inward direct investment. There is no evidence that raising it somewhat, as previously planned, will cut investment. And as far as individual entrepreneurs are concerned, cutting taxes is likely to have little effect on the desire to invest and expand businesses. The motivation of entrepreneurs is only partly to do with the money. A major motivation is the sense of achievement in building a successful business.

Creating investment zones with lower taxes, no business rates and lower regulations may encourage firms to set up there. But much of this could simply be diverted investment from elsewhere in the country, leaving overall investment little changed.

To assess these questions, the government needs to model the outcomes and draw on evidence from elsewhere. So far this does not seem to have happened. They government did not even present a forecast of the effects of its policies on the public finances, something that the OBR normally presents at Budget time. This was one of the reasons for the collapse in confidence of sterling and gilts (government bonds) in the days following the mini-Budget.

Effects on aggregate demand

Cutting taxes and financing them from borrowing will expand aggregate demand. In Figure 1, the AD curve will also shift to the right and this will push up prices. Inflation is already a serious problem in the economy and unfunded tax cuts will make it worse. Higher inflation will result in the Bank of England raising interest rates further to curb aggregate demand. But higher interest rates, by raising borrowing costs, are likely to reduce investment, which will have a negative supply-side effect.

The problem here is one of timing. Market-orientated supply-side policies, if they work to increase potential GDP, will take time – measured in years rather than months. The rise in aggregate demand will be much quicker and will thus precede the rise in supply. This could therefore effectively kill off the rise in supply as interest rates rise, the exchange rate falls and the economy is pushed towards recession. Indeed, the mini-Budget immediately sparked a run on the pound and the exchange rate fell.

The rising government debt may force the government to make cuts in public expenditure. Rather than cutting current expenditure on things such as nurses, teachers and benefits, it is easier to cut capital expenditure on things such as roads and other infrastructure. But this will have adverse supply-side effects.

Effects on income distribution

Those advocating market-orientated supply-side policies argue that, by making GDP bigger, everyone can gain. They prefer to focus on the size of the national ‘pie’ rather than its distribution. If the rich initially gain, the benefits will trickle down to the poorest in society. This trickle-down theory was popular in the 1980s with politicians such as Margaret Thatcher and Ronald Reagan and, more recently, with Republican presidents, such as Goerge W Bush and Donald Trump. There are two problems with this, however.

The first, which we have already seen, is whether such policies actually do increase the size of the ‘pie’.

The second is how much does trickle down. During the Thatcher years, income inequality in the UK grew, as it did in the USA under Ronald Reagan. According to an IMF study in 2015 (see the link to the IMF analysis below), policies that increase the income share of the poor and the middle class do increase growth, while those that raise the income share of the top 20 per cent result in lower growth.

After the mini-Budget was presented, the IMF criticised it for giving large untargeted tax cuts that would heighten inequality. The poor would gain little from the tax cuts. The changes to income tax and national insurance mean that someone earning £20 000 per year will gain just £167 per year, while someone earning £200 000 will gain £5220. What is more, the higher interest rates and higher prices resulting from the lower exchange rate are likely to wipe out the modest gains to the poor.

Podcast

• A Walk on the Supply Side

BBC Radio 4 podcast, Duncan Weldon (1/11/22)

Articles

• At a glance: What’s in the mini-budget?

BBC News (23/9/22)

• Mini-budget: What it means for you and your finances

BBC News, Kevin Peachey (23/8/22)

• Will this huge tax cutting gamble pay off?

BBC News, Faisal Islam (23/9/22)

• Kwasi Kwarteng faces U-turn on tax or spending cuts

BBC News, Faisal Islam (28/9/22)

• Nearly 300 UK mortgage deals pulled in a day as pound’s fall heralds rate rise

The Guardian, Zoe Wood (27/9/23)

• Rationale behind abolition of 45p tax rate reflects failed ideology

The Guardian, Arun Advani, David Burgherr and Andy Summers (29/9/23)

• The UK’s ‘Trussonomics’ crashes the pound and leaves investors shaking their heads

CNN, Allison Morrow (26/9/23)

• Mini budget: will Kwasi Kwarteng’s plan deliver growth?

The Conversation, Steve Schifferes (23/9/23)

• Only a U-turn by the government or the Bank of England will calm UK financial markets

The Conversation, Campbell Leith (28/9/22)

• IMF gives damning verdict on Britain’s tax cuts

CNBC, Hannah Ward-Glenton (28/9/23)

• Lasting effects of ‘mini’ Budget will be felt far beyond the trading floors

Today News, Torsten Bell (1/10/23)

Analysis

• Causes and Consequences of Income Inequality: A Global Perspective

IMF Staff Discussion Notes, Era Dabla-Norris, Kalpana Kochhar, Nujin Suphaphiphat, Franto Ricka and Evridiki Tsounta (15/6/15)

• Mini-Budget response

Institute for Fiscal Studies, Stuart Adam, Isaac Delestre, Carl Emmerson, Paul Johnson, Robert Joyce, Isabel Stockton, Tom Waters, Xiaowei Xu and Ben Zaranko (23/9/22)

Questions