Perhaps you didn't see other graphs, but life expectancy in Europe started to shot up sharply, and it did so precisely in the 1950s, the founding of the European integration movement. This is because it marked the beginning of progress for all ...
I am sure you find similar graphs for Canada, Australia, New Zealand, Japan, and a lot of other countries. This is because it marked the begging of progress for all in Canada, Australia, New Zealand, Japan, and a lot of other countries.
This shows clearly that democracy is the best form of government.
This has nothing to do, however, that Mao was the biggest killer in history, as many historians agree. Under Mao's regime, more people have died than under any other dictators, including Hitler and Stalin.