Fluid intelligence but not vocabulary has increased in Britain, 1979–2008

New standardizations of the Coloured and Standard Progressive Matrices in Britain in 2007 and 2008 show that on the Coloured Progressive Matrices the intelligence of 4 to 11 year olds increased over the years 1982–2007 by 8 IQ points, representing a gain of 3.2 IQ points a decade, and on the Standard Progressive Matrices the intelligence of 7 to 15 year olds increased over the years 1979–2008 by 6.2 IQ points, representing a gain of 1.85 IQ points a decade. IQ gains were greater among those at the low ability level. New standardizations of the Crichton Vocabulary Scale and the Mill Hill Vocabulary Scale in Britain in 2007 and 2008 show a marginal decline on the Crichton Vocabulary Scale among 4 to 11 year olds, and a marginal increase on the Mill Hill Vocabulary Scale among 7 to 15 year olds, suggesting there has been little change in vocabulary over the same time periods. These results are more consistent with the improvements in nutrition theory than with the improvements in education and greater cognitive stimulation theories of the secular gains in intelligence.