During the 1970s and 1980s Ceaușescu determined that Romania should be completely debt-free and sought to repay its foreign debt ahead of the repayment schedule agreed to by the country's creditors. To accomplish this, he exported for sale any products or materials of value, while the little inferior food and products remained was sold on the domestic market. Opposition was ruthlessly crushed and expressions of discontent were stifled by the ubiquitous Securitate, the secret police. As a result, in order to survive, more and more people began to transact business through barter trade and other informal economic means. achieved his goal, but at a huge cost to nearly all sectors of the country. Since the anti-Ceaușescu revolution in 1989, restructuring of the coal sector, the country's economic contraction, and a shift toward natural gas all contributed to a significant decrease in both production and consumption of coal in Romania. Production declined by 57%, from 66.4 million short tons (Mmst) in 1989 to 28.6 Mmst in 1998. Consumption also fell more than 60%, from 77.7 Mmst in 1989 to 30.8 Mmst in 1998.