It takes an extra three years to finish elementary school for low-income students, PNAD, the national household survey, shows. Costs of finishing school rise each year until it is impossible to attend, meaning that low-income students also have the lowest rates for completing school. Rio de Janeiro began a program in 2009 called the Reforço Escolar testing all students in the beginning of the school year to discover all who are not yet at grade level. Those who are not receive two weeks of in-depth tutoring. São Paulo and Paraná have also created programs to help those who are behind, either due to being low-income or for other reasons.