East West Bancorp's (NASDAQ:EWBC) fourth-quarter earnings of $0.49 left the stock down slightly in yesterday's trading. But that earnings tally is in the past. What's really important about East West's release was what it says about the future, and I think savvy investors are now looking at three reasons East West is now an even better buy than it was before.

1. Stellar asset quality
East West's fourth quarter represents the 13th consecutive quarter that it has reported total nonperforming assets under 1% of total assets. After coming in at an already low 0.66% at the end of the third quarter, the ratio declined further to 0.63% at year end. This is a truly remarkable number for a bank of East West's size, and truly indicates the bank's devotion to maintaining a clean balance sheet.

East West also goes out of its way to limit the risks associated with its assets, checking in well above the required "well capitalized" ratio of 10%, reporting a total risk-based capital ratio of 16.1%, with over $800 million in reserves above the required ratio.

2. Returning value to shareholders 
Even as East West has built up its safety buffer, it's been returning value to its shareholders. During the past year, the bank purchased 6% of its outstanding shares, reducing total shares outstanding by 9.1 million. The bank also doubled its dividend during the course of 2012, from $0.05 to $0.10 per share.

In conjunction with the fourth-quarter numbers, East West's board continued the trend, authorizing a new $200 million stock repurchase plan, as well as another increase in the dividend up to $0.15 per share. Throw in a modest 7.7% increase to the share price during the past year, and there's good reason for shareholders to be pretty happy with the bank.

3. Net interest margin and income
East West saw a decrease in its net interest margin over the course of the year, declining from 4.13% at the end of 2011 to 3.84% at the end of 2012. In the meantime, net interest also declined over the year from $204.0 million to $198.4 million, and you would expect investors to react poorly to that outcome. However, the bank still managed to increase net income every quarter this year, and ended the year with record net income of $281.7 million for the third consecutive year. 

Foolish bottom line
East West calls itself the "financial bridge between the United States and Greater China," and while I am in no position to judge the accuracy of that quote, they seem to be among the better-run banks in the Pacific region. With a clean balance sheet and a growing dividend, it might be time to further investigate East West Bancorp. While earnings releases are important, it is just as important to look beyond the top- and bottom-line numbers to see if there is something you are missing.

Fool contributor Robert Eberhard has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.