Between the 1917 and 1925 seasons, the Philadelphia Phillies had the lowest winning percentage by a team, winning 40.0 percent of the time.

	TEAM	W%	W	L	G	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	PA	TB	XBH	SH	AVG	OBP	SLG	OPS
1	Phillies	.400	532	798	1,338	46,283	5,674	12,494	2,129	450	679	5,102	3,383	277	4,709	709	51,156	17,560	3,258	1,213	.270	.323	.379	.703
2	Athletics	.401	537	801	1,348	45,830	5,492	12,244	1,956	555	503	4,866	3,625	327	4,737	693	51,225	16,819	3,014	1,443	.267	.325	.367	.692
3	Braves	.415	553	781	1,343	45,850	5,129	12,146	1,624	635	273	4,470	3,469	285	4,150	840	51,048	15,859	2,532	1,444	.265	.321	.346	.666
4	Red Sox	.460	614	720	1,346	44,937	5,469	11,855	2,064	543	251	4,808	4,170	340	3,754	767	51,194	15,758	2,858	1,747	.264	.331	.351	.682
5	Cardinals	.489	655	684	1,347	46,473	6,109	13,096	2,083	724	532	5,442	3,460	247	4,170	964	51,585	18,223	3,339	1,405	.282	.335	.392	.727
6	Browns	.497	662	671	1,341	45,965	6,321	13,159	2,154	651	525	5,547	3,899	303	3,591	952	51,865	18,190	3,330	1,698	.286	.346	.396	.742
7	Tigers	.502	674	668	1,353	46,062	6,685	13,276	2,173	706	329	5,879	4,808	305	3,590	940	53,107	17,848	3,208	1,932	.288	.359	.387	.747
8	Robins	.507	678	660	1,347	46,665	5,722	12,871	1,787	681	401	5,066	3,136	239	3,489	737	51,409	17,223	2,869	1,369	.276	.325	.369	.694
9	Cubs	.509	684	661	1,353	45,560	5,779	12,425	1,933	553	414	5,063	3,688	294	4,019	1,130	51,198	16,706	2,900	1,656	.273	.331	.367	.698
10	Senators	.510	682	656	1,353	45,855	5,914	12,582	1,940	688	259	5,186	4,216	435	4,155	1,167	52,191	16,675	2,887	1,685	.274	.341	.364	.705
11	White Sox	.518	694	647	1,347	45,470	6,238	12,681	2,065	624	289	5,471	4,528	355	3,762	1,259	52,288	16,861	2,978	1,935	.279	.349	.371	.720
12	Pirates	.532	713	626	1,346	45,982	5,911	12,711	1,791	857	317	5,209	3,524	265	3,469	1,500	51,209	17,167	2,965	1,438	.276	.332	.373	.705
13	Reds	.547	734	608	1,349	45,475	5,779	12,723	1,806	832	269	5,096	3,411	308	3,232	1,136	50,781	17,000	2,907	1,587	.280	.334	.374	.708
14	Indians	.547	734	608	1,348	45,641	6,696	13,146	2,518	655	307	5,932	4,919	358	3,554	966	52,790	17,895	3,480	1,872	.288	.362	.392	.754
15	Yankees	.565	754	580	1,344	45,720	6,470	12,655	2,025	617	749	5,821	4,310	283	4,518	751	51,926	18,161	3,391	1,613	.277	.343	.397	.740
16	Giants	.601	803	534	1,345	46,304	6,541	13,109	1,980	665	587	5,789	3,686	313	4,040	1,100	51,487	18,180	3,232	1,184	.283	.340	.393	.733