After the Second World War, the major religions began to decline, while the previously insignificant religion of Islam began to increase in numbers. During the 1960s and 1970s, pillarization began to weaken and the population became less religious. In 1971, 39% of the Dutch population were members of the Roman Catholic Church; by 2014, their share of the population had dropped to 23.3% (church-reported KASKI data), or to 23.7% (large sample survey by Statistics Netherlands in 2015). The proportion of adherents of Protestantism declined in the same period from 31% to 15.5%. A significant percentage of the population adheres to other Protestant churches and the Old Catholic Church. With only 49.9% of the Dutch currently (2015) adhering to a religion, the Netherlands is one of the least religious countries of Europe, after the Czech Republic and Estonia. During the 1960s through 1980s, religion lost its influence on the Dutch politics and as a result in the 1980s and 1990s the Dutch policy on women's rights, abortion, euthanasia, homosexuality and prostitution became very liberal.