Table 4.

Estimated increase in life expectancy at birth and number of life years lived attributed to ${\mathrm{PM}}_{2.5}$ concentration reductions between 1980 and 2010 for individuals born in 1990, 2000, 2010, and 2050.

Year of birth	Estimated increase in life expectancy at birtha,b,c		Cumulative number of life years gaineda,b,d
	Men	Women
1990	0.01	0.01	7,800
2000	0.19	0.18	140,000
2010	0.43	0.61	640,000
2050	0.94	0.87	4,400,000

^aEstimates rounded to two significant figures.

^bThe all-cause risk coefficient from Krewski et al. (2009) was used to estimate changes in life expectancy at birth and life years, under the assumption that ${\mathrm{PM}}_{2.5}$ has no effect on mortality prior to the age of 30.

^cEstimated increase in life expectancy at birth due to declines in ${\mathrm{PM}}_{2.5}$ from 1980–2010, relative to the estimated life expectancy for the same birth cohort if ${\mathrm{PM}}_{2.5}$ concentrations were fixed at 1980 concentrations.

^dEstimated cumulative increase in life years among adults $\ge 30\mathrm{y}$ of age in each birth cohort due to declines in ${\mathrm{PM}}_{2.5}$ concentrations from 1980–2010 compared with the estimated life years for the same birth cohort if ${\mathrm{PM}}_{2.5}$ concentrations were fixed at 1980 concentrations.