As your quote says, that study is talking about birth years, not the year they were tested. Since it's based on conscription it's around age 19-20, so the decli

As your quote says, that study is talking about birth years, not the year they were tested. Since it's based on conscription it's around age 19-20, so the decline was measured between ~1994 and 2011. Your lead paragraph also states as much: "...At some point in the mid-1990s, IQ scores in these countries tipped into decay, losing roughly one-fifth to one-quarter of a point per year..."