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REGULATORY REQUIREMENTS AND MATTERS (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Actual |  |
Total Capital (to Risk-Weighted Assets), Amount | $ 3,082,945,000 | $ 2,753,599,000
Tier I Capital (to Risk-Weighted Assets), Amount | 2,686,627,000 | 2,405,452,000
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Amount | 2,650,413,000 |
Tier I Capital (to Average Assets), Amount | 2,686,627,000 | 2,405,452,000
Risk weighted assets | $ 25,232,575,000 | 21,931,486,000
Adjusted quarterly average total assets |  | $ 28,501,115
Total Capital (to Risk-Weighted Assets), Ratio (as a percent) | 12.20% | 12.60%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent) | 10.70% | 11.00%
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Ratio (as a percent) | 10.50% |
Tier I Capital (to Average Assets), Ratio (as a percent) | 8.50% | 8.40%
Minimum Requirement |  |
Total Capital (to Risk-Weighted Assets), Ratio (as a percent) | 8.00% | 8.00%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent) | 6.00% | 4.00%
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Ratio (as a percent) | 4.50% |
Tier I Capital (to Average Assets), Ratio (as a percent) | 4.00% | 4.00%
Well Capitalized Requirement |  |
Total Capital (to Risk-Weighted Assets), Ratio (as a percent) | 10.00% | 10.00%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent) | 8.00% | 6.00%
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Ratio (as a percent) | 6.50% |
Tier I Capital (to Average Assets), Ratio (as a percent) | 5.00% | 5.00%
East West Bank |  |
Actual |  |
Total Capital (to Risk-Weighted Assets), Amount | $ 3,039,524,000 | $ 2,590,173,000
Tier I Capital (to Risk-Weighted Assets), Amount | 2,754,201,000 | 2,316,615,000
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Amount | 2,754,201,000 |
Tier I Capital (to Average Assets), Amount | $ 2,754,201,000 | 2,316,615,000
Risk weighted assets |  | 21,875,078
Adjusted quarterly average total assets |  | $ 28,418,340
Total Capital (to Risk-Weighted Assets), Ratio (as a percent) | 12.10% | 11.80%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent) | 11.00% | 10.60%
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Ratio (as a percent) | 11.00% |
Tier I Capital (to Average Assets), Ratio (as a percent) | 8.80% | 8.20%
Minimum Requirement |  |
Total Capital (to Risk-Weighted Assets), Ratio (as a percent) | 8.00% | 8.00%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent) | 6.00% | 4.00%
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Ratio (as a percent) | 4.50% |
Tier I Capital (to Average Assets), Ratio (as a percent) | 4.00% | 4.00%
Well Capitalized Requirement |  |
Total Capital (to Risk-Weighted Assets), Ratio (as a percent) | 10.00% | 10.00%
Tier I Capital (to Risk-Weighted Assets), Ratio (as a percent) | 8.00% | 6.00%
Tier 1 Common Equity Capital (to Risk-Weighted Assets), Ratio (as a percent) | 6.50% |
Tier I Capital (to Average Assets), Ratio (as a percent) | 5.00% | 5.00%
Reserve Requirement |  |
Daily average reserve requirement | $ 395,600,000 | $ 325,700,000

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