Alexey Strygin calculated that the historical increase in expected age at death is 5,5–27 times slower than LEV requires
Alexey Strygin calculated that the historical increase in expected age at death is 5,5–27 times slower than LEV requires
On August 3, Alexey Strygin published a demographic analysis of progress toward longevity escape velocity. At the frontier, expected age at death increased by 0,4–1,8 years per decade. LEV requires an increase of ten years.
LEV, or longevity escape velocity, begins when expected age at death increases by at least one year during each calendar year. A person ages by one year, while their expected date of death moves back by at least one year. Strygin examined how close actual demographic trends have come to this rate.
The author used the UN life tables for 1950–2023. For each year, he selected the five countries with the highest expected age at death and calculated their median. The countries in this group changed over time, so the series represents the best results among national populations rather than the history of a single country. Strygin averaged the male and female figures within each country.
The gap widens with age. At birth, the frontier advanced by 1,8 years per decade. The corresponding gains were 1,4 years at age 50, 0,6 at age 80, and 0,4 at age 90. To reach LEV, these rates would need to increase by 5,5, 7,3, 16,7, and 27 times, respectively.
Strygin also examined age-specific mortality. In the Gompertz model, the risk of death increases exponentially with age: each additional year multiplies the risk by an approximately constant factor. Using data for frontier countries and ages 35–89, the author estimated that the mortality curve has shifted downward since 1950, while its slope has increased slightly. The probability of dying at each age has fallen, but the rate at which this probability increases with age has not slowed. Aubrey de Grey proposed a similar test when discussing whether the time required for the risk of death to double was increasing in the oldest age groups.
The data for 80- and 90-year-olds show a slight acceleration. In his methodology, Strygin mechanically extrapolates this acceleration. The earliest threshold crossing occurs in 2459 for the measure with a starting age of 30.