Chart 3

Net interest margins for varying asset size groups are diverging after a decade of convergence.
Date (YYYYMM)	Net interest margin for banks with assets under $100 million (percent)	Net interest margin for banks with assets between $100 million and $1 billion (percent)	Net interest margin for banks with assets between $1 billion and $10 billion (percent)	Net interest margin for banks with assets over $10 billion (percent)
198403	4.3100	3.53	2.97	2.7
198406	4.5500	3.8	3.125	2.78
198409	4.5400	3.8	3.165	2.7
198412	4.4100	3.65	3.16	3.11
198503	4.4800	3.645	2.84	2.805
198506	4.6500	3.84	3.17	2.9
198509	4.7400	3.88	3.07	2.85
198512	4.6000	3.88	3.205	2.86
198603	4.4600	3.77	3.28	2.785
198606	4.4100	3.77	3.25	2.815
198609	4.3300	3.68	3.305	2.68
198612	4.2500	3.68	3.305	2.88
198703	4.1900	3.64	3.27	2.78
198706	4.2600	3.77	3.43	2.66
198709	4.3000	3.77	3.35	2.55
198712	4.2800	3.75	3.38	2.58
198803	4.1600	3.59	3.27	2.45
198806	4.2300	3.71	3.32	2.46
198809	4.3500	3.88	3.405	2.435
198812	4.3300	3.92	3.4	3.085
198903	4.3400	3.94	3.435	2.585
198906	4.3700	3.95	3.4	2.37
198909	4.3100	3.85	3.28	2.715
198912	4.2800	3.86	3.33	2.98
199003	4.2000	3.82	3.39	3.03
199006	4.2800	3.91	3.42	3.01
199009	4.3100	3.96	3.44	3.055
199012	4.3000	3.94	3.45	3.28
199103	4.1700	3.9	3.515	3.22
199106	4.2900	4	3.62	3.46
199109	4.4200	4.11	3.78	3.44
199112	4.3900	4.13	3.82	3.71
199203	4.4700	4.25	3.91	3.76
199206	4.5900	4.38	4.09	3.79
199209	4.7100	4.46	4.22	3.99
199212	4.6900	4.52	4.31	4.27
199303	4.5700	4.44	4.27	4.175
199306	4.6200	4.48	4.32	4.13
199309	4.6300	4.42	4.27	3.995
199312	4.5400	4.38	4.28	3.935
199403	4.3900	4.27	4.19	3.77
199406	4.5600	4.42	4.28	3.965
199409	4.6700	4.5	4.31	4.01
199412	4.6800	4.51	4.26	4.045
199503	4.6000	4.395	4.19	3.86
199506	4.5600	4.37	4.15	3.805
199509	4.5400	4.37	4.16	3.835
199512	4.5100	4.38	4.23	3.81
199603	4.3900	4.29	4.16	3.93
199606	4.4800	4.37	4.19	3.95
199609	4.5600	4.41	4.22	3.99
199612	4.5400	4.42	4.21	4.075
199703	4.4200	4.32	4.11	4.12
199706	4.5400	4.415	4.14	4.07
199709	4.5600	4.4	4.14	4.06
199712	4.5100	4.37	4.14	4.1
199803	4.3900	4.27	4.05	4.01
199806	4.4200	4.29	4.09	3.98
199809	4.4200	4.27	4.12	3.95
199812	4.3000	4.205	4.01	3.93
199903	4.1600	4.11	3.97	3.93
199906	4.2600	4.21	4.06	3.915
199909	4.3800	4.26	4.035	3.935
199912	4.3900	4.27	4.01	3.915
200003	4.3600	4.21	3.94	3.83
200006	4.4300	4.25	3.95	3.87
200009	4.3800	4.17	3.885	3.83
200012	4.3000	4.09	3.82	3.71
200103	4.1300	4	3.82	3.785
200106	4.1100	4.02	3.905	3.9
200109	4.1100	4.07	3.93	3.9
200112	4.1200	4.13	4.03	3.94
200203	4.1200	4.14	3.97	4.02
200206	4.2800	4.24	4.055	4.02
200209	4.3200	4.23	3.985	3.97
200212	4.2100	4.14	3.91	3.82
200303	4.0400	3.99	3.785	3.71
200306	4.0600	3.96	3.72	3.6
200309	4.0700	3.965	3.66	3.62
200312	4.1000	3.99	3.74	3.615
200403	4.0300	3.935	3.72	3.52
200406	4.0800	3.96	3.73	3.55
200409	4.1600	4.04	3.785	3.52
200412	4.1700	4.06	3.825	3.55
200503	4.0900	4.01	3.76	3.53
200506	4.1700	4.09	3.815	3.445
200509	4.2300	4.12	3.82	3.415

Source: FDIC