In 2002, the gross primary enrollment rate was 103 percent, and the net primary enrollment rate was 55 percent. Gross and net enrollment ratios are based on the number of students formally registered in primary school and therefore do not necessarily reflect actual school attendance. In 1996, 51.7 percent of children ages 7 to 14 years were attending school. As of 2001, 49 percent of children who started primary school were likely to reach grade 5. At the end of 2003 an estimated 370,000 children in Mozambique were AIDS orphans. It is estimated that HIV/AIDS could lead to a decline in teacher numbers by 2010.