What it means: how long a baby born now would live on average if death rates stayed as they are, worked out from three years of deaths at a time to smooth out swings. Gains slowed sharply after 2011 and fell back during Covid. The solid line is the simple average of women and men; the fainter lines are women (solid) and men (dotted). No numeric target applies, so the status compares with the previous period: a change of 0.1 years or more counts.

Source: ONS, national life tables, UK, period life expectancy at age 0.