Question

What is the Preston curve? Explain its shape.

Answer 1

The Preston Curve gives a relationship between the Real per capita income of a country and the life expectancy of the people of that country. What the preston curve suggests is that People in richer or developed countries live longer than people in poorer countries. But as income rises to higher levels, this relationship flattens out i.e at high income levels, a change in income has very little impact on the life expectancy. There are other factors on which life expectancy is dependent, but Samuel H Preston in his study in 1975 used empirical data to find a relationship between real GDP per capita and life expectance.

As discussed above, the curve flattens out for higher income levels.