In international tests administered to students in dozens of nations, U.S. fourth graders rank in the top 30% of countries for reading and for math. However, by the age of 15, U.S. students drop to the bottom 45% for reading and to the bottom 15% for math. Randi Weingarten, president of one of the largest U.S. teachers' unions, has blamed the subpar performance of older U.S. students on education funding, but the average annual spending per U.S. pupil is 39% above the average of these nations.