The wealth-management business holds a particular allure in China owing to the surging number of millionaires. The country had 1.26 million high-net worth individuals at the end of last year, double from 2010, said China Merchants Bank Co. and Bain & Company in their 2015 survey of the country's private wealth industry. Rich Chinese are increasingly embracing private-banking services, with 65% engaging financial professionals to manage their assets managed, up from 30% in 2009, the survey showed.