People at lower income levels simply don’t live as long. It may be a combination of factors affecting this group, including more stress, less access to good health care and poorer lifestyle decisions related to smoking, obesity and exercise.
To test this on a country-by-country basis, we combine two statistics. One is income inequality as measured using the Gini co-efficient, which is a number between zero and one. If it was zero, then everyone’s income would be the same. If there was no middle class, the Gini coefficient would be closer to one. The other statistic is GDP per capita, which is a rough measure of overall wealth.
The chart combines these two statistics and plots them against the average life expectancy measured from birth. Each dot in the chart represents a relatively affluent country, including most western European and Scandinavian countries, China, Russia, Japan and South Korea, the larger South American countries, Canada, the United States and Mexico.
By fitting a trendline to the chart, we see a strong correlation between longevity and income. Canada falls right on the trendline and most other countries are fairly close to it.
There are some outliers though. Russia is one. Shorter lifespans there may have something to do with the unusually high rate of alcohol abuse. Japan is another outlier, but on the high side. Note Japan’s very low obesity rate – about 3 per cent.
The biggest outlier though, is income inequality is higher in the U.S. than in Canada or most European countries, although GDP per capita is also high, so the two factors should cancel each other out – but they don’t.
Something else is keeping the average lifespan low in the U.S. The most likely possibilities, in order of decreasing importance, are: obesity, uneven access to health care, drug-overdose deaths and the high murder rate, which is three times as high as Canada’s.
Frederick Vettese is former chief actuary of Morneau Shepell and author of the PERC retirement calculator (perc-pro.ca)
