Any general statement as to whether the secular trend of a society is eugenic or dysgenic depends upon a reliable calibration of the measurement of general intelligence. Richard Lynn set the mean IQ of the United Kingdom at 100 with a standard deviation of 15, and he calculated the mean IQs of other countries in relation to this “Greenwich IQ”. But because the UK test scores are declining, the present paper recalibrates the mean IQ 100 to the average of seven countries having a historical mean IQ of 100. By comparing LynnVanhanen-IQ with PISA scores and educational attainment of native and foreign born populations transformed into IQ, we confirmed brain gain and brain drain in a number of nations during recent decades. Furthermore, the growth of gross domestic product per capita can be derived as a linear function of the percentage of people with an IQ above 105 and its underlying frequency of a hypothetical major gene of intelligence.