Preschool enrollment is the percentage of preschool age children enrolled in preschool (typically children ages three and four). Preschool education serves two major functions: preparing students to succeed in primary school and providing childcare to enable parents of young children to work. The availability of preschool is inconsistent across countries, with some making it mandatory, some providing free public options, and some relying on private schools, for which parents must pay tuition. Higher enrollment in preschool can be indicative of better financial stability and greater social mobility with parents able to secure the educational opportunity for their child and pursue professional opportunities of their own.