sentences:  Singapore's non-resident workforce increased 170% from 248,000 in 1990 to 670,000 in 2006 (Yeoh 2007).By 2010, the non-resident workforce had reached nearly 1.09 million, of these 870,000 were low-skilled foreign workers in Singapore; another 240,000 were skilled foreign worker, better-educated S-pass or employment pass holders.Malaysia is the main source of immigrants in Singapore (386,000 in 2010), followed by China, Hong Kong, and Macau, then South Asia, Indonesia, and other Asian countries.