Figure 6. Life Expectancy by Income in Norway vs the United States.

The solid lines represent predicted life expectancy estimated from a fractional polynomial of income. Life expectancy was estimated by a combination of actual mortality rates (individuals aged 40-76 years), forecasted mortality rates (individuals aged 77-90 years), and uniform sex-specific mortality rates (individuals aged ≥91 years) and was presented as expected age at death for individuals aged 40 years. Estimates were based on comparable populations in Norway and the United States according to Chetty et al.¹