Legally, only non-profit trusts and societies can run schools in India. They will have to satisfy a number of infrastructure and human resource related criteria to get Recognition (a form of license) from the government. Critics of this system point out that this leads to corruption by school inspectors who check compliance and to fewer schools in a country that has the largest adult illiterate population in the world. While official data does not capture the real extent of private schooling in the country, various studies have reported unpopularity of government schools and an increasing number of private schools. The Annual Status of Education Report (ASER), which evaluates learning levels in rural India, has been reporting poorer academic achievement in government schools than in private schools. A key difference between the government and private schools is that the medium of education in private schools is English while it is the local language in government schools.