Age-Adjusted Excess Mortality Since January of 2020

Back in March, the ONS published a chart showing age-adjusted excess mortality since the start of 2020. This chart provides the best guide to the pandemic’s impact on deaths, for reasons I’ve explained before.

In short, it’s based on all-cause deaths, rather than ‘official’ Covid deaths, so it gets around the problem of deciding whether people who died of Covid would have died anyway. In addition, it’s based on age-standardised rates, meaning that it takes into account the changing age-structure of the population.

However, the ONS’s chart stops in February, so it’s a little out of date. Here I’ve produced a similar chart for England that goes all the way up to September of 2021:

Note: my chart looks slightly different from the ONS’s version because theirs is based on weekly data, whereas mine is based on monthly data. But the overall pattern from January 2020 to February 2021 is basically the same.

Clearly, the pandemic was at its deadliest in April of 2020, when the age-standardised mortality rate reached almost 200% of the five-year average. Since then, it has gone above and below the expected value of 100%. Note that the winter peak in January was only 21% higher than the five-year average.

If we take the average value since the start of 2020, it comes out as 5.8%. This is consistent with a recent ONS analysis, which reported an almost identical figure for the relative cumulative age-standardised mortality rate up to July. (The corresponding figure for Wales was only 3.5%.)

Interestingly, the average since the end of the first wave is less than 2%, meaning the pandemic hasn’t caused very many deaths over the past 15 months. This probably owes to a combination of factors: better treatments; better shielding of vulnerable populations; the vaccination program, and the gradual build-up of natural immunity.

Excessive focus on ‘official’ death numbers has led to a distorted picture of the pandemic’s impact on mortality – both in terms of the total increase and the distribution over time. Tracking age-adjusted excess mortality provides a much-needed corrective.