Hack Wilson has the highest on-base percentage + RBIs in a month, with 53.5 in August 1930.

Interpreted as:

highest obp+rbi by a player in a month

	NAME	OBP+RBI	OBP	RBI	MONTH	G	AB	R	H	2B	3B	HR	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	GIDP	AVG	SLG	OPS
1	Hack Wilson H. Wilson	53.5	.496	53	August 1930	30	113	27	45	3	1	13	22	0	17	1		144	89	17	9		.398	.788	1.284
2	Joe DiMaggio J. DiMaggio	53.48	.483	53	August 1939	31	131	37	53	7	0	14	19	1	4	0		154	102	21	3	2	.405	.779	1.262
3	Lou Gehrig L. Gehrig	50.46	.459	50	July 1930	35	136	37	51	12	5	12	21	0	17	1		161	109	29	4		.375	.801	1.260
4	Rudy York R. York	50.43	.429	50	August 1937	30	113	27	41	5	2	18	13	0	14	1		126	104	25	0		.363	.920	1.349
5	Pie Traynor P. Traynor	49.48	.479	49	August 1928	32	139	34	64	11	5	1	4	1	1	4		150	88	17	6		.460	.633	1.112
6	Lou Gehrig L. Gehrig	48.53	.530	48	August 1935	35	126	38	48	11	2	10	39	1	11	3		166	93	23	0		.381	.738	1.268
7	Mel Ott M. Ott	47.5	.500	47	June 1929	33	121	35	41	12	0	11	37	2	7	2		165	86	23	5		.339	.711	1.211
8	Babe Ruth B. Ruth	47.41	.408	47	August 1929	31	118	31	41	7	2	15	12	0	16	0		133	97	24	3		.347	.822	1.230
9	Hank Greenberg H. Greenberg	46.42	.420	46	June 1935	31	130	27	47	12	4	12	13	0	17	1		145	103	28	2		.362	.792	1.212
10	Lou Gehrig L. Gehrig	45.49	.486	45	August 1937	30	112	29	40	3	5	11	26	2	15	1		140	86	19	0		.357	.768	1.254
11	Hal Trosky Sr. H. Trosky Sr.	45.43	.434	45	July 1936	33	144	28	58	9	3	11	7	1	10	0		153	106	23	1		.403	.736	1.170
12	Gus Bell G. Bell	45.38	.385	45	June 1953	32	131	26	43	8	1	11	11	1	11	0	0	144	86	20	1	4	.328	.656	1.041
13	Cy Williams C. Williams	44.44	.437	44	May 1923	30	124	29	44	8	0	15	17	1	9	5		142	97	23	0		.355	.782	1.219
14	Joe DiMaggio J. DiMaggio	44.4	.401	44	August 1938	36	155	44	52	10	6	7	16	1	4	0		172	95	23	0		.335	.613	1.014
15	Joe DiMaggio J. DiMaggio	43.5	.504	43	July 1937	29	121	40	52	10	6	15	17	1	9	2		139	119	31	0		.430	.983	1.487
16	Ed Morgan E. Morgan	43.48	.480	43	July 1930	34	131	38	52	13	2	9	20	1	14	4		156	96	24	4		.397	.733	1.213
17	Babe Ruth B. Ruth	43.48	.475	43	September 1927	27	103	29	39	3	1	17	19	0	15	3		126	95	21	4		.379	.922	1.398
18	Ty Cobb T. Cobb	43.46	.459	43	May 1925	30	128	33	49	8	8	5	17	1	0	1		147	88	21	1		.383	.688	1.146
19	Rudy York R. York	43.46	.459	43	August 1943	31	112	29	40	4	0	17	21	0	19	0		134	95	21	1	2	.357	.848	1.307
20	George Selkirk G. Selkirk	43.35	.354	43	August 1935	35	148	19	44	6	3	3	13	0	7	0		162	65	12	1		.297	.439	.793
21	Hank Greenberg H. Greenberg	42.47	.471	42	May 1937	31	119	32	45	8	5	9	20	1	15	0		140	90	22	0		.378	.756	1.228
22	Ripper Collins R. Collins	42.43	.430	42	June 1935	29	116	25	43	9	0	11	12	0	7	0		129	85	20	1		.371	.733	1.162
23	Freddie Lindstrom F. Lindstrom	42.43	.429	42	June 1929	33	150	40	58	8	3	7	11	0	7	0		169	93	18	8		.387	.620	1.049
24	Rogers Hornsby R. Hornsby	42.43	.428	42	July 1922	35	141	28	54	16	3	10	11	0	14	3		154	106	29	2		.383	.752	1.179
25	Bob Meusel B. Meusel	42.42	.423	42	July 1920	33	124	25	49	17	0	7	6	0	18	0		135	87	24	5		.395	.702	1.125