While the NUAT for freshmen and sophomores is held in March, June, September, and November, seniors take tests in March, April, July, and October to avoid overlapping with months when the CSAT Simulation is held (June and September). These two tests are appropriate for relative evaluations such as measuring average score, percentage, or ranks since the PCSAT has more similar sample groups to the CSAT than private mock tests do. The College Scholastic Ability Test Simulation (CSAT Simulation, ) is hosted by KICE, and unlike the NUAT, anyone who is eligible for the CSAT can also apply for this test. The CSAT Simulation was introduced after the CSAT failed to set the proper difficulty level in 2001 and 2002. It was first implemented in 2002, and during its early years, it was held only once a year, in September. Starting from 2004, it is being held twice a year, every June and September. The exam covers everything in the curriculum for the Korean and second language sections; for other sections, two-thirds of what the CSAT covers. However, the September exam covers everything in every section just like the CSAT. The number of questions and test time per section is same as those of the CSAT. Since the Liberation of Korea, South Korea has changed the methods of university and college admission at least twelve times. Some argue the number of changes can be extended to sixteen. The policies ranged from sometimes allowing colleges to choose on their own to outlawing hagwons. Because of this, parents and students had difficult times in adjusting to the changes. Some argue that the constant changes show an instability of the system as well as the sensitivity of the admission process to public opinion. The very first methods of university and college admissions were left to the choice of the university. Each university was allowed to do as they like. The first form of CSAT appeared in the beginnings of 1960. The Supreme Council for National Reconstruction established an early form of CSAT from 1962 to 1963. It served as a qualification test for the students. However, due the small number of students passing the tests, the colleges soon had a shortage of students. The process was also criticized to have led to an inefficient selection of students, Due to this, the government scrapped the policy from 1964 to 1968. A similar policy was adopted in 1969 by the Third Republic of South Korea. The new test was called "Preliminary College Entrance Examination" (대학입학예비고사).