That improvement slowed after about 2011 is established for the UK and for several other high-income countries; the US went further and saw life expectancy fall before the pandemic. The pandemic then produced the largest fall in life expectancy since the Second World War, and most countries had recovered to or above their 2019 level by 2023 or 2024. What is not established is why the earlier slowdown happened. The candidate explanations — the exhaustion of cardiovascular gains, rising obesity and diabetes, drug and alcohol deaths in some countries, severe influenza seasons, and the effects of austerity on older and poorer people — each account for some of the change in some places, and no decomposition has apportioned them across countries. The steady direction reflects that: the fact of the stall is not in dispute and the explanation has not moved. The post-pandemic years are now the test of whether the pre-2011 rate of improvement returns, continues at the slower rate, or has been reset.