As a result, while Korea had one of the widest proboy gender gaps in 2012, girls outperformed boys in 2015, although the difference was not statistically significant. Colombia had the widest pro-boy mathematics gender gap of all PISA-participating countries/economies in 2012, but was able to close it significantly -even among the country’s highest-achieving students. While boys’ performance remained stable between 2012 and 2015, girls did 20 points better on average, with the highest-achieving improving by 28 points.