【正确答案】The ever-increasing migrant workers are becoming powerful consumers and this change will drive China's economic evolution. In 2012, blue collars shifted from surplus to shortage, which made their incomes rise faster than any other significant consumer groups. With income increasing, they spent 677 billion on goods and services in 2012. It was equivalent to 1.5 times total consumer spending in Indonesia that year. According to the Chinese government, the consumption activities of migrant workers contribute a lot to the transformation of Chinese GDP growth mode, from over-reliance on investment towards more consumption-driven growth.

【答案解析】 1.第1、2句联系紧密，因此采用合译法，使用and连接，and除了表达并列含义之外，还可以起到承接上句的作用，此处理解为“而”。
   2.“由过剩转为短缺”的“由……转为”，译成shift from...to...(方向的移动或改变)，不可用transform(指外形或面貌的彻底改变)。
   3.“这使得农民工的收入……”这一句是上句造成的结果，因此可合译成一个句子，处理成which引导的非限制性定语从句。which指代“蓝领劳动力由过剩转为短缺”。
   4.“随着收入的增长，农民工群体……”是一个长句，考虑到前面句子都采用了合译处理，因此，将此句分译成两个短句，避免句式单调。以“相当于”作为拆分点，后句增译it，指代数字677 billions。
   5.末句虽长，但从句型上看是简单陈述句。“在促使……方面发挥重大作用”译成contribute a lot to...。此句翻译的难点是contribute to的宾语部分“中国GDP增长模式由……转向……”，即中国GDP增长模式的转变，因此译成the transformation of Chinese GDP growth mode。此处说的是经济模式的变革，因此“转向”译成trans-formation更贴合文意。