If you wanted to figure out where Asian exports were headed, U.S. manufacturing data used to be a logical place to start. The U.S. is buying more goods from neighbors such as Mexico instead of Asia, and the shale-gas boom has kept demand within the country, said Christy Tan, head of markets strategy for Asia at National Australia Bank Ltd. The recovery in the world’s biggest economy is also more services-oriented this time, and some of the increase in wealth and employment is being used to pay off debt rather than on consumption, she said. “Asia’s definitely lagging behind the U.S.