How many entries exist for each party's governments and each decade. This shows where the record is thin, so a quiet period reads as a gap in coverage, not as inactivity.
A 13 August 1990 office memorandum reserved 27% of central civil vacancies for Other Backward Classes. The Supreme Court upheld it in 1992 with a creamy-layer exclusion and a 50% overall limit.
A 2019 constitutional amendment allows up to 10% reservation in education and public jobs for economically weaker sections outside SC, ST and OBC categories. The Supreme Court upheld it 3-2 in November 2022.