Confused about deficits and debt? Try taking a bath!

In its report A Distorted Debate: the need for clarity on Debt, Deficit and Coalition Aims, the Centre for Policy Studies claims that the public is confused by economic terminology surrounding the government’s finances. We try and understand this confusion and offer a bath-time solution!

In a survey conducted for the Centre for Policy Studies only 10 per cent of Britons knew that despite cuts to parts of the government’s spending plans, the stock of public sector debt (also known as the national debt) is expected to rise by a further £60 billion by 2015. Rather, 47 per cent of respondents thought that debt would have fallen by this amount.

The confusion is not terribly surprising because there are two important core economic concepts that can confuse: stocks and flows. To try to help we will show how reference to a bath tub can hopefully eliminate the confusion. However, first, let us considerthe Coalition government’s principal fiscal objective. Its so-called fiscal mandate is for the cyclically-adjusted current budget to be in balance by 2015/16. In simple terms, the government wants to be able afford its day-to-day expenditures by this date, after taking into account where the economy is in the business cycle. In other words, if the economy’s output was at its sustainable or potential level in 2015-16 the government should be able to raise sufficient taxes to meet what it refers to as current expenditures. This would still allow the government to borrow to fund investment expenditure, e.g. infrastructural projects, which are enjoyed or consumed over a period of time.

An important thing to note about the fiscal mandate is that the government can expect to need to borrow money in order to afford its current expenditures up to 2015/16. Even beyond this date, assuming that the mandate can be met, it is likely to need money to afford capital expenditures. This is where we introduce the bath tub. Think of government spending as water coming through the bath taps while the taxes that government collect are water leaving through the plug hole. Therefore, spending and tax receipts are flows. If the water pouring into the bath (spending) is greater than the water leaving the bath (tax receipts), the level of water in the bath will rise. You can think of the water level in the bath as the stock of national debt. Therefore, if government is spending more than it receives it needs to borrow money. Borrowing is therefore a flow concept too. As it borrows, the stock of debt (the amount of water in our bath tub) rises.

So we know that government will continue to borrow in the near future. What it is hoping to be able to do, year by year, is begin to borrow less. It wants the deficit to fall. Then, if it can meet its target, it will at least be able to afford current expenditure (after adjustment for where the economy is in the cycle) by 2015/16. As the deficit begins to decline then the stock of debt will rise less quickly. But, the bath tub will continue to fill because more is flowing through the taps than is leaving through the plug hole. However, it will fill less quickly.

What our use of the bath tub analogy demonstrates is the confusion that can be caused when economic terminology is misused. It is important that the terms debt and deficit be used carefully and correctly. Therefore, the next time you are sitting in bath see if you can be the next Chancellor by understanding these key economic concepts.

Don’t know your debts from your deficit? You’re not alone Independent, Andrew Johnson (27/8/12)
Government unlikely to meet deficit targets, warns CPS Telegraph (27/8/12)
Coalition ‘most unlikely’ to meet key economic goals by next election Guardian, Andrew Sparrow (27/8/12)
Public ‘don’t know their debt from their deficit’ Public Finance, Vivienne Russell (28/8/12)
George Osborne ‘still failing to stop rising deficit’ Daily Express (28/8/12)


  1. Explain the difference between the concepts of government deficits and government debt?
  2. Explain what will happen to both the size of the government’s deficit and to its stock of debt if borrowing begins to decline.
  3. Can the stock of government debt fall if the government continues to borrow? Can the ratio of the stock of government debt fall relative to GDP (i.e. Debt/GDP), if government continues to borrow?
  4. With examples, explain the differences between the government’s current and investment (capital) expenditures.
  5. What are the economic arguments for trying to cut the deficit quickly or more slowly?