However, " n ot all markets are going through this crisis right now," he adds.

On the whole, analysts expect both MasterCard and Visa to post healthy second-quarter profits this week. Visa, which reports late Wednesday, is expected to post 48 cents a share in earnings. It made $314 million, or 39 cents a share in the first quarter -- the only quarter so far when the firm has reported earnings on a GAAP basis since it went public.

MasterCard, set to report Thursday, is expected to post earnings of $2.01 a share, according to average estimates compiled by Thomson Reuters. It recorded a profit of $253 million, or $1.85 a share, in the year-earlier quarter.

Visa's stock is up by roughly one-third since its first day of trading. MasterCard shares, which went public in May 2006, have risen more than fivefold, even as the financial sector has plummeted amid the credit crisis. Both companies, which issue cards to bank partners and collect a fee on each consumer transaction, are aggressively expanding globally as consumers and businesses shift from paper to electronic forms of payment.

The companies also do not extend credit to consumers. Credit delinquencies and defaults from lending to consumers have pressured earnings at two other card companies, American Express ( AXP) and Discover Financial Services ( DFS), as well as several banks with large credit card market share.

But even these two bright spots of the financial sector have seen their stocks taken hits recently, as the financial sector remains volatile one year into the credit crisis. Investors are worried that the U.S. economic slowdown could expand internationally, hurting Visa's and MasterCard's growth plans. Visa shares are down 13% this month, while MasterCard's have fallen roughly 4%.

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