Comment by robocat

> The cost of nails has fallen by 95% over the last century

No it hasn't!

A century ago, some nails cost 2.5% of disposable income, and now the same nails cost 2.3% - only a little cheaper.

The cost of nails has remained remarkably consistent for a century. The problem is that you have ignored the depreciation of money.

Let's assume California prices and income and pick a bigger retail package of nails as you might use for building a house. The numbers used to calculate percentages: in 1926 a 50lb keg of 4" nails was $2.75 and median after tax income might be $108 per month. In 2026 a 50lb carton of 4" nails is $106 and income might be $4,516. Albeit I assume nails are now more readily available and the quality of nails is likely better; and perhaps I should have compared galvinised nail prices.