Arriaga Decomposition

Arriaga decomposition is a demographic technique that breaks down the difference in life expectancy between two life tables — two countries, two time points, or two groups — into the contributions of mortality change at each age. Introduced by Eduardo Arriaga in 1984, it tells the analyst not just that life expectancy rose or fell, but exactly which ages drove the change, separating the direct effect of mortality change within an age interval from the indirect effect of the extra survivors that change passes on to older ages.