A sharp decline in coal mining deaths was reported in China for the first four months this year, following the government's efforts to improve safety in the industry.The mortality rate fell 39 percent from the same period last year, according to an ongoing international forum about mining safety held in Hefei, capital of east China's Anhui Province.China's coal mines are among the deadliest in the world.The booming coal-dependent economy, lax regulations and inefficiency are usually blamed for the high death rate.The government has called for better safety systems and forced smaller, more dangerous mines to close in the hope of reducing accidents.The death toll dropped to 2,433 in 2010 from 5,938 in 2005, while the country's annual coal production jumped to 3.24 billion tonnes from 2.15 billion...