Poverty rates have not been curbed despite steady economic growth. HIV became an increasing problem in 1998, but the epidemic has since been almost curbed. A night-time curfew was imposed and press freedom was greatly curbed. Economic growth was curbed due to Western trade barriers combined with the 1973 oil crisis. Coal demand was curbed by competition from other energy sources. Hoover eventually curbed cooperation with the CIA, because Angleton refused to relent on this hypothesis. Post-surgery, overeating is curbed because exceeding the capacity of the stomach causes nausea and vomiting. High wages and Aboriginal land claims have also curbed expansion. Other laws curbed immigration from Southern and Eastern Europe. To prevent a king from becoming a tyrant, his political powers must be curbed. In 1832, Metternich introduced laws that curbed fledgling liberal movements in Germany. However, he regularly curbed his own viewpoints, preferring to arrive at decisions by consensus. The president's powers were curbed somewhat. Marshall regularly curbed his own viewpoints, preferring to arrive at decisions by consensus. The British Army claims to have curbed the IRA insurgency by 1972, after Operation Motorman.