Article: The late 1980s saw a series of liberalising economic reforms within Libya designed to cope with the decline in oil revenues. In May 1987, Gaddafi announced the start of the "Revolution within a Revolution", which began with reforms to industry and agriculture and saw the re-opening of small business. Restrictions were placed on the activities of the Revolutionary Committees; in March 1988, their role was narrowed by the newly created Ministry for Mass Mobilization and Revolutionary Leadership to restrict their violence and judicial role, while in August 1988 Gaddafi publicly criticised them, asserting that "they deviated, harmed, tortured" and that "the true revolutionary does not practise repression." In March, hundreds of political prisoners were freed, with Gaddafi falsely claiming that there were no further political prisoners in Libya. In June, Libya's government issued the Great Green Charter on Human Rights in the Era of the Masses, in which 27 articles laid out goals, rights and guarantees to improve the situation of human rights in Libya, restricting the use of the death penalty and calling for its eventual abolition. Many of the measures suggested in the charter would be implemented the following year, although others remained inactive. Also in 1989, the government founded the Al-Gaddafi International Prize for Human Rights, to be awarded to figures from the Third World who had struggled against colonialism and imperialism; the first year's winner was South African anti-apartheid activist Nelson Mandela. From 1994 through to 1997, the government initiated cleansing committees to root out corruption, particularly in the economic sector.

Now answer this question: In what year did the "Revolution within a Revolution" begin?
1987