3. Things you need to know about this release

What are the most important terms I need to know?

Public sector net borrowing excluding public sector banks (PSNB ex) measures the gap between revenue raised (current receipts) and total spending (current expenditure plus net investment (capital spending less capital receipts)). Public sector net borrowing is often referred to by commentators as “the deficit”.

The public sector net cash requirement (PSNCR) represents the cash needed to be raised from the financial markets over a period of time to finance the government’s activities. This can be close to the deficit for the same period but there are some transactions, for example, loans to the private sector, which need to be financed but do not contribute to the deficit. It is also close but not identical to the changes in the level of net debt between two points in time.

Public sector net debt excluding public sector banks (PSND ex) represents the amount of money the public sector owes to private sector organisations including overseas institutions, largely as a result of issuing gilts and treasury bills, less the amount of cash and other short-term assets it holds.

While borrowing (or the deficit) represents the difference between total spending and receipts over a period of time, debt represents the total amount of money owed at a point in time.

The debt has been built up by successive government administrations over many years. When the government borrows (that is, runs a deficit), this normally adds to the debt total. So reducing the deficit is not the same as reducing the debt.

If you’d like to know more about the relationship between debt and deficit, please refer to our article The debt and deficit of the UK public sector explained.

What does the public sector include?

In the UK, the public sector consists of five sub-sectors: central government, local government, public non-financial corporations, Bank of England and public financial corporations (or public sector banks).

Unless otherwise stated, the figures quoted in this bulletin exclude public sector banks (that is currently only Royal Bank of Scotland (RBS)), as the reported position of debt (and to a lesser extent borrowing) would be distorted by the inclusion of RBS's balance sheet (and transactions). This is because government does not need to borrow to fund the debt of RBS, nor would surpluses achieved by RBS be passed on to government, other than through any dividends paid as a result of government equity holdings.

The sub-sector breakdown of public sector net borrowing is summarised in Table PSA2 in the Public sector finances Tables 1 to 10: Appendix A dataset.

Should I look at monthly or financial year-to-date data to understand public sector finances?

A financial year is an accounting period of 12 months running from 1 April one year to 31 March the following year. For example, the financial year ending March 2016 comprises the months from April 2015 to March 2016.

Due to the volatility of the monthly data, the cumulative financial year-to-date borrowing figures provide a better indication of the position of the public finances than the individual months.

Are our figures adjusted for inflation?

All monetary values in the public sector finances (PSF) bulletin are expressed in terms of “current prices‟, that is, they represent the price in the period to which the expenditure or revenue relates and are not adjusted for inflation.

In order to compare data over long time periods, to aid international comparisons and provide an indication of a country’s ability to service borrowing and debt, commentators often discuss changes over time to fiscal aggregates in terms of gross domestic product (GDP) ratios. GDP represents the value of all the goods and services currently produced by the UK economy in a period of time.

Are our figures adjusted for seasonal patterns?

All monetary values in the PSF bulletin are not seasonally adjusted. We recommend you use year-on-year comparisons (be it cumulative financial year-to-date or individual monthly borrowing figures) rather than making month-on-month comparisons.

Are our monthly figures likely to change over time?

Each PSF bulletin contains the first estimate of public sector borrowing for the most recent period and is likely to be revised in later months as more data become available.

In publishing monthly estimates, it is necessary to use a range of different types of data sources. Some of these are subject to revision as budget estimates (forecasts) are replaced by out-turn data and these then feed into the published aggregates.

In addition to those that stem from updated data sources, revisions can also result from methodology changes. An example of the latter is the changes that were due to the introduction of improved methodology for the recording of Corporation Tax, Bank Corporation Tax Surcharge receipts and Bank Levy implemented in the PSF estimates released in February 2017.

How is the debt interest paid by the government affected by movements in the level of RPI?

Index-linked gilts, a form of government bond, are indexed to the Retail Prices Index (RPI). When the RPI rises, the inflation uplift that applies to index-linked cash flows (both regular coupon payments and final payment at gilt maturity) also rises. If the RPI should fall, the inflation uplift would also fall. In this way, the returns to the investor from holding index-linked gilts are maintained in real terms – as measured by the RPI.

Taking £100 as the unit price for a gilt, an index-linked gilt will pay more than £100 at redemption if the RPI increases over the life of the gilt. Similarly, if the RPI increases over the life of the gilt each coupon payment will be higher than the previous one; while if the RPI were to decrease, a coupon payment could be lower than the previous one.

Both the uplift on coupon payments and the uplift on the redemption value are recorded as debt interest paid by the government, so month-on-month there can be sizeable movements in payable government debt interest as a result of movements in the RPI.