Sentences of Enduring Value

First, on general principles it’s not clear what one learns from very short-term movements in relative wages… Second, more specifically, the period since 1995 includes a major boom-bust cycle in high-technology industries. The technology bubble of the late 1990s probably elevated the education premium, while the subsequent bust caused that premium to deflate. As a result, inferences from the movement in inequality during the first few years after the tech bust should be taken with a grain of salt.

Paul Krugman 2008 working paper (pdf)