My friend Tarik sent me the chart above pursuant to an unrelated thought experiment. It comes from the Economist, which compiled figures from little-e economist Angus Maddison and the UN to plot economic output and percentage of total human-years lived against centuries. A human-year is a particularly useful unit of history if you prefer the broad trend hypothesis to the Great Man Theory. As the Economist puts it, “if people do make history, as this democratic view suggests, then two people make twice as much history as one.” Fact: two people, each living 70 years, experience more human time—that is, history—than one person living 70 years. Given that the life expectancy of your typical eighth-century serf was like 28, the lion’s share of human experience has taken place in the last century.
The 20th century was also the first period in which the percentage of total economic output exceeded portion of total years lived—by a lot, you’ll notice.* While the human-years put in since 1900 account for about 35% of the total, the same period produces almost 80% of economic output. The conclusion is obvious: those of us who are currently alive are contributing way more than our fair share to the historical pie. Did you know that almost 50% of the living in this history is done by people who contribute less than 2.5% of our economic output? That’s called a free ride, and it’s part of the reason history sucks today.