When Daniel Sichel, professor of economics, isn’t doing research on economic growth, technology, and economic measurement, he enjoys woodworking—in particular making furniture. One day, while looking at a catalog of tools, he saw a listing for old-fashioned cut nails. He started wondering how much those nails would have cost in the 19th century, and he began looking at prices that economic historians had gathered. “As I got into it more, I realized that this was actually a really interesting window into centuries of economic change,” says Sichel.

Sichel used techniques of price measurement to create a continuous series of nail prices going back to 1695. He detailed his findings in a recent National Bureau of Economic Research working paper. First, the real price of nails fell by a factor of 10 from the late 1700s to the middle of the 20th century. When nails were more expensive, they were quite precious, Sichel says. “So people did things like, if there was an abandoned building, they would burn it, and then somebody would pick through the ashes to pull all the nails out.” Nails were almost a half a percent of GDP in 1810—comparable to today’s share of household purchases of personal computers. Sichel was surprised that since the 1950s, however, the price of nails has increased, which he attributes to materials becoming more expensive and the U.S. focusing on making specialty nails while importing standard nails.

Another of Sichel’s recent projects was serving as chair of a National Academy of Sciences panel on how to modernize the Consumer Price Index. “If you’re focused on how you measure prices over three or four hundred years, a lot of the questions that come up are similar—different scale, different timespan, but similar—to questions and issues that government statisticians would face when they’re putting together a measure of inflation like the Consumer Price Index,” he says.