Any debate over how schooling is financed has first to get to grips with the types of schools that make up the melting pot of education here. Government schools - At the base of most education systems are government schools, owned and financed by government and run under its education authority. Here, they account for about 7 per cent of school places. Aided schools - The bulk of free education takes place in aided schools, which may occupy government-built campuses but are run by independent school sponsoring bodies. These schools have all their costs met by government, with the sums allocated based on fixed pupil-teacher and pupil-class ratios. Direct Subsidy Scheme (DSS) - To promote diversity in schooling, the government launched the DSS in 1991. Aided and private schools deemed to have attained a high educational standard can switch to this status. They receive subsidies based on the average unit cost of an aided school place for each local student enrolled. But a sliding scale related to their top-up fees means that the more they charge, the less grant they receive. DSS schools can decide on their own curriculum and entrance requirements. English Schools Foundation - The ESF, set up by ordinance in 1967 to offer native English education, was financed on a similar basis to the DSS, with students receiving the equivalent subsidy as those in aided schools, although there is no sliding scale linked to fees. The subvention was capped in 1999, at around $300 million. Places are offered on a first come first served basis but English competency is required and priority given to those who cannot be educated in local schools. Private schools (Private schools may be local or international) - Before universal education was introduced in the 1970s, those who failed to secure aided places turned to the private sector. The bulk of local private schools charged low fees and as a result were not well resourced nor elite in reputation. There are notable exceptions, such as the primary section of the prestigious St Paul's Convent School. International schools, numbering about 60, are run by national communities, religious organisations and education foundations or as profit-making enterprises. The top schools represent the elite of the private sector. Government support for the major schools is limited to land grants and interest-free loans. In 1999 the government boosted the sector by launching the private independent school (PIS) scheme. Sponsoring bodies receive capital grants for school construction but must raise their own financing for extra resources as well as all running costs. At least 70 per cent of their students must be local. They are free to choose their own curriculum - local or international - and set entrance requirements and fees.