Well, there are only 27 ratified amendments total, the first 10 of which were passed at once, so 17 in 248 years makes 32 a little more than twice the average a

Well, there are only 27 ratified amendments total, the first 10 of which were passed at once, so 17 in 248 years makes 32 a little more than twice the average amount of time, but they also tend to happen in clusters, and gaps between clusters have been longer than this before, so I don't think it's even all that anomalous.