Every three years, 15-year-old students are being tested in the fields of reading, mathematics and science. Each time, one of those 3 domains is the main focus of assessment. In 2000 it was reading, 2003 mathematics and in 2006 science. In 2009, the second cycle of PISA started. For the second time reading was the main focus. In 2012, mathematics will be the main focus and in 2015 science (as well as in the first cycle).