Mastercard stock is trading down about 10% from recent highs. The shares look cheaper, but still aren't cheap.Mastercard (MA 2.00%) has a long history of success behind it as one of the two largest retail financial transaction processors in the world. You'll probably find the Mastercard logo on a credit or debit card in your own wallet. That business success has attracted its share of stock success as well.While the stock has generally been on a consistent path up in value, it has retreated around 10% from ...