You apparently overlooked the other methods of payment that can be used by online purchasers. China has several methods other than CC's which can be used.
Also the 2% - 3% figure is based on China's total population which includes those 800 million farmers. A more relevant figure would be the percentage of the population who are potential computer buyers who hold a credit card. In addition you have to take into account the number of Chinese who will acquire credit cards in the future. It is an emerging technology like computer use.
Credit Card Use Mounts
Shanghai people are expanding their purchasing methods from the cash only payment to financial vehicle. All the four state-owned banks' local branches reported surges in credit card business during the Labor Day holiday week.
Statistics from the Industrial and Commercial Bank of China indicated it had handled 90 million yuan (US$1 million) in transactions for its card users through its POS system, 220 percent up over the last "golden week" in the Spring Festival holiday.
The China Construction Bank also reported 23.8 million yuan credit card trading, 226 percent up over the Spring Festival week. On May 6, it received record daily business for its "dragon card" since the credit card service was launched.
The business for the Bank of China's "great wall card" jumped 360 percent, and the Communications Bank of China managed 10 million yuan trading for its "pacific card" users, reported today's Wenhui Daily.
Another thing that's noteworthy, as insiders pointed out, is tourists from other provinces constituted the main card users.
As far as the "great wall card" is concerned, local holders used it to pay more than 6 million yuan for around 3,000 bills, while the incoming travelers spent 13 million yuan for around 6,800 deals.
Market Data 
Markets 
AI
