Original sentence: , which is larger than more recent measurements.A 2006 study by Dickens and Flynn found that the gap closed by about 5 or 6 IQ points between 1972 and 2002.A decrease in Black-White differences on school achievement tests has also been reported, in which the difference has shrunk from about 1.2 to about 0.8 standard deviations.Disagreements over testing methodologies and methods of aggregating and validating results across many decades have contributed to the controversy about whether or not scores are converging, and what it means if they are.Murray has claimed that these improvements may have stalled for people born after the early 1970s.The black men inducted into the US armed forces during World War II averaged about 1.5 standard deviations below their white counterparts
Edited sentence: Flynn claims that the Black-White gap has reduced throughout the 20th century.For example, the black men inducted into the US armed forces during World War II averaged about 1.5 standard deviations below their white counterparts.However, Murray claims that these improvements may have stalled for people born after the early 1970s.The overall average Black-White gap has reduced by one third over the course of the 20th century.This improvement is also reflected in Black-White differences on school achievement tests, which have shrunk from about 1.2 to about 0.8 standard deviations