best winning% with a minimum of 100 decisions as a pitcher in the 1930s

Between the 1930 and 1939 seasons, Lefty Grove had the best win percentage with 100+ decisions, at .724.

	NAME	W%	DEC	W	L	G	GS	ERA	SO	CG	SHO	SV	IP	H	ER	R	HR	BB	HBP	GF	TBF	WP	K/9	BB/9	K/BB	HR/9	K%	BB%	WHIP	BABIP	RA	ERA-	FIP	FIP-	H/9	PRAA
1	Lefty Grove L. Grove	.724	275	199	76	351	268	2.91	1,313	197	26	31	2399.0	2,344	776	907	93	639	22	72	10,054	16	4.93	2.40	2.05	0.35	13.1	6.4	1.24	.282	3.40	62	3.33	73	8.79	326
2	Johnny Allen J. Allen	.706	153	108	45	212	182	3.73	838	94	12	4	1406.1	1,323	583	654	66	547	27	22	5,970	50	5.36	3.50	1.53	0.42	14.0	9.2	1.33	.280	4.19	84	3.67	85	8.47	102.6
3	Firpo Marberry F. Marberry	.686	102	70	32	218	116	3.82	369	50	6	27	1029.0	1,043	437	491	70	309	7	73	4,356	8	3.23	2.70	1.19	0.61	8.5	7.1	1.31	.270	4.29	87	4.18	97	9.12	11.1
4	Lefty Gomez L. Gomez	.650	254	165	89	322	278	3.24	1,337	163	26	10	2234.2	2,031	804	949	122	904	15	28	9,505	30	5.38	3.64	1.48	0.49	14.1	9.5	1.31	.268	3.82	75	3.79	90	8.18	98
5	Dizzy Dean D. Dean	.648	227	147	80	305	219	2.96	1,144	151	26	31	1908.1	1,845	628	736	91	432	27	76	7,903	12	5.40	2.04	2.65	0.43	14.5	5.5	1.19	.282	3.47	75	3.19	78	8.70	192.3
6	Carl Hubbell C. Hubbell	.644	292	188	104	383	303	2.71	1,281	197	31	30	2596.2	2,437	782	917	147	467	39	66	10,584	34	4.44	1.62	2.74	0.51	12.1	4.4	1.12	.265	3.18	69	3.42	86	8.45	163.9
7	Red Ruffing R. Ruffing	.641	273	175	98	334	298	3.59	1,260	201	28	9	2439.0	2,327	972	1,123	150	858	24	31	10,351	24	4.65	3.17	1.47	0.55	12.2	8.3	1.31	.270	4.14	83	3.93	93	8.59	77.1
8	Monte Pearson M. Pearson	.634	145	92	53	201	171	4.00	652	86	4	4	1295.2	1,262	576	658	71	681	6	21	5,687	40	4.53	4.73	0.96	0.49	11.5	12.0	1.50	.278	4.57	88	4.34	98	8.77	9.7
9	Lon Warneke L. Warneke	.629	229	144	85	318	247	3.23	877	146	24	11	2021.0	1,993	725	845	126	555	21	46	8,471	45	3.91	2.47	1.58	0.56	10.4	6.6	1.26	.271	3.76	83	3.83	96	8.88	35.3
10	Bill Lee B. Lee	.602	176	106	70	240	201	3.21	640	110	23	8	1570.2	1,562	560	645	84	483	13	24	6,590	31	3.67	2.77	1.33	0.48	9.7	7.3	1.30	.275	3.70	82	3.88	96	8.95	30.1
11	Schoolboy Rowe S. Rowe	.602	133	80	53	189	143	4.11	540	77	15	7	1126.2	1,187	515	581	69	325	9	34	4,803	13	4.31	2.60	1.66	0.55	11.2	6.8	1.34	.290	4.64	89	3.80	84	9.48	88.5
12	Wes Ferrell W. Ferrell	.596	285	170	115	323	293	4.08	867	207	16	8	2345.1	2,554	1,062	1,251	124	911	18	28	10,347	32	3.33	3.50	0.95	0.48	8.4	8.8	1.48	.288	4.80	87	4.25	93	9.80	86.7
13	Tommy Bridges T. Bridges	.595	252	150	102	309	266	3.76	1,207	156	25	8	2083.0	2,015	870	1,021	138	902	29	32	9,033	41	5.22	3.90	1.34	0.60	13.4	10.0	1.40	.278	4.41	81	4.10	91	8.71	93.4
14	Alvin Crowder A. Crowder	.593	194	115	79	266	196	4.16	543	100	8	12	1592.2	1,717	737	818	95	472	10	43	6,837	14	3.07	2.67	1.15	0.54	7.9	6.9	1.37	.284	4.62	94	4.10	95	9.70	36.4
15	Hal Schumacher H. Schumacher	.591	198	117	81	274	231	3.38	623	99	19	4	1736.2	1,716	652	775	95	593	16	25	7,376	44	3.23	3.07	1.05	0.49	8.4	8.0	1.33	.268	4.02	89	4.07	104	8.89	-34
16	Monte Weaver M. Weaver	.587	121	71	50	201	135	4.36	297	57	2	4	1052.0	1,137	510	591	62	435	5	38	4,632	17	2.54	3.72	0.68	0.53	6.4	9.4	1.49	.280	5.06	99	4.48	104	9.73	-25.3
17	Elden Auker E. Auker	.581	148	86	62	226	161	4.40	394	76	10	2	1234.2	1,390	603	695	76	439	29	39	5,438	7	2.87	3.20	0.90	0.55	7.2	8.1	1.48	.292	5.07	94	4.36	96	10.13	27.8
18	Pat Malone P. Malone	.577	163	94	69	275	164	3.93	703	79	8	23	1397.1	1,433	610	717	76	504	33	86	6,076	35	4.53	3.25	1.39	0.49	11.6	8.3	1.39	.285	4.62	96	3.99	96	9.23	26.6
19	Roy Mahaffey R. Mahaffey	.574	115	66	49	218	128	5.01	358	45	0	5	1042.0	1,167	580	661	83	442	23	42	4,703	30	3.09	3.82	0.81	0.72	7.6	9.4	1.54	.285	5.71	110	4.78	107	10.08	-38.2
20	Tex Carleton T. Carleton	.573	164	94	70	259	185	3.92	720	87	15	6	1458.1	1,490	635	702	93	514	35	54	6,296	37	4.44	3.17	1.40	0.57	11.4	8.2	1.37	.283	4.33	101	3.99	99	9.20	5.4
21	Heinie Meine H. Meine	.573	103	59	44	142	119	3.88	180	53	6	2	887.1	1,000	383	461	43	251	18	13	3,867	12	1.83	2.55	0.72	0.44	4.7	6.5	1.41	.284	4.68	99	4.21	104	10.14	-18
22	Guy Bush G. Bush	.566	198	112	86	316	194	4.02	498	99	9	16	1628.1	1,808	727	836	98	466	18	75	7,059	37	2.75	2.58	1.07	0.54	7.1	6.6	1.40	.286	4.62	101	4.16	104	9.99	-30.7
23	Mel Harder M. Harder	.562	281	158	123	385	285	3.74	813	134	16	22	2326.0	2,557	967	1,168	101	692	41	71	10,102	22	3.15	2.68	1.17	0.39	8.0	6.9	1.40	.290	4.52	81	3.88	86	9.89	163.6
24	Charlie Root C. Root	.562	203	114	89	377	187	3.50	818	96	10	30	1829.1	1,870	711	812	114	466	47	123	7,716	15	4.02	2.29	1.76	0.56	10.6	6.0	1.28	.280	3.99	89	3.83	95	9.20	43.2
25	Curt Davis C. Davis	.558	165	92	73	246	151	3.50	381	79	11	19	1263.2	1,368	492	579	79	262	25	71	5,317	12	2.71	1.87	1.45	0.56	7.2	4.9	1.29	.282	4.12	83	3.96	91	9.74	59.2