Chart of the week: Government bond yields

On 9 December, the benchmark ten-year government bond yield for major western economies ranged from -0.61% for investors in German Bunds through to 0.95% for US Treasury Bonds and 1.02% for Australia Government Bonds, as illustrated in the #icaewchartoftheweek.

One of the more astonishing developments of the last decade or so has been the arrival of an era of ultra-low or negative interest rates, even as governments have borrowed massive sums of money to finance their activities. This is not only a consequence of weak economic conditions and the slowing of productivity-led growth, but it has also been driven by the monetary policy actions of central banks through quantitative easing operations that have driven down yields by buying long-term fixed interest rate government bonds in exchange for short-term variable rate central bank deposits.

For bond investors this has been a wild ride, with the value of existing bonds sky-rocketing as central banks have come calling to buy a proportion of their holdings, crystallising their gains. The downside is the extremely low yields available to debt investors on fresh purchases of government bonds, which in some cases involve paying governments for the privilege of doing so.

Yields vary according to maturity, with yields on UK gilts ranging from -0.08% on two-year gilts through to 0.26% for 10-year gilts (as shown in the chart) up to 0.81% on 30-year gilts. In practice, the UK issues debt with an average maturity between 15 and 20 years, so the current average cost of its financing is higher than that shown in the chart at between 0.48% and 0.77% being the yields on 15-year and 20-year gilts respectively. This has the benefit of locking in low interest rates for longer, in contrast with most of the other countries shown that tend to issue debt with an average maturity of less than ten years.

Quantitative easing complicates the picture, as by repurchasing a significant proportion of government debt and swapping it for central bank deposits, central banks have reversed the security of fixed interest rates locked in to maturity with a variable rate exposure that will hit the interest line immediately if rates change. 

In theory, this should not be a problem, as higher interest rates are most likely to accompany stronger economic growth and hence higher tax revenues with which to pay the resultant higher debt interest bills, but in practice treasury ministers are not so sanguine. In leveraging public balance sheets to finance their responses to COVID-19 – on top of the legacy of debt from the financial crisis – governments have significantly increased their exposure to movements in interest rates, just as other fiscal challenges are growing more pressing.

Expect to hear a lot more over the coming decade about the resilience of public finances as governments seek to reduce gearing and reduce their vulnerability to the next unexpected crisis, whenever that may occur.