Sino-Japanese War. Malaya's two other major ethnic groups, the Indians and Malays, escaped the worst of the initial Japanese maltreatment. The Japanese wanted the support of the Indian community to free India from British rule. They also considered the Malay's not to be a threat. All three races were encouraged to assist Japanese war efforts by providing finance and labour. Some 73,000 Malayans were thought to have been coerced into work on the Thai-Burma Railway, with an estimated 25,000 dying. The Japanese also took the railway track from Malacca and other branch lines for construction of the Siam-Burma railway. About 150,000 tons of rubber was taken by the Japanese, but this was considerably less than Malaya exported prior to the occupation. Because Malaya produced more rubber and tin than Japan was able to utilize Malaya lost its export income. Real per capita income fell to about half its 1941 level in 1944 and less than half the 1938 level in 1945. Prior to the war Malaya produced 40% of the world's rubber and a high proportion of the world's tin. It imported more than 50% of its rice requirements, a staple food for its population. The Allied blockade meant that both imports and the limited exports to Japan were dramatically reduced. During the occupation the Japanese replaced the Malayan dollar with their own version. Prior to occupation, in 1941, there was about Malaya $219 million in circulation. Japanese currency officials estimated that they had put $7,000 to $8,000 million into circulation during occupation. Some Japanese army units had mobile currency printing presses and no record was kept of the quantity or value of notes printed. When Malaya was liberated there was $500 million of uncirculated currency held by the Japanese in Kuala Lumpur. The unrestrained printing of banknotes in the final months of the war created hyperinflation with the Japanese money becoming valueless at the end of the war. During the war the Allies dropped propaganda leaflets stressing that the Japanese issued money would be valueless when Japan surrendered. This tactic was suggested by Japanese policy makers as one of the reasons for the currencies falling value as Japanese defeats increased. Although a price freeze was put in place in February 1942, by the end of the war prices in Malaya were 11,000 times higher than at the start of the war. Monthly inflation reached over 40% in August 1945.