Between the 2008 and 2017 seasons, the Houston Astros had the worst winning percentage by a team, winning 45.6 percent of the time.

	TEAM	W%	W	L	G	AB	R	H	2B	3B	HR	RBI	BB	HBP	SO	SB	CS	PA	TB	XBH	SH	SF	IBB	GIDP	AVG	OBP	SLG	OPS
1	Astros	.456	739	880	1,619	54,863	6,752	13,848	2,774	245	1,635	6,397	4,646	512	12,503	1,103	443	60,864	22,017	4,654	452	391	283	1,231	.252	.315	.401	.716
2	Padres	.457	741	879	1,620	54,309	6,277	13,064	2,498	316	1,408	5,954	4,952	506	13,111	1,072	361	60,744	20,418	4,222	578	399	367	1,088	.241	.308	.376	.684
3	Mariners	.461	747	873	1,620	55,196	6,431	13,657	2,576	209	1,588	6,117	4,594	470	12,182	909	352	60,976	21,415	4,373	341	375	315	1,174	.247	.309	.388	.697
4	Rockies	.467	756	864	1,620	55,537	7,681	14,872	2,935	435	1,779	7,322	5,045	435	12,680	983	411	62,092	24,014	5,149	655	420	410	1,179	.268	.331	.432	.764
5	Marlins	.468	758	860	1,618	55,147	6,699	14,011	2,666	339	1,464	6,369	4,892	524	12,740	897	324	61,571	21,747	4,469	614	394	420	1,206	.254	.319	.394	.713
6	Twins	.469	761	861	1,622	55,639	7,309	14,397	2,868	337	1,500	6,945	5,240	445	11,875	889	345	62,128	22,439	4,705	342	462	321	1,246	.259	.325	.403	.728
7	Pirates	.476	770	848	1,619	54,917	6,629	13,760	2,763	314	1,442	6,341	4,899	647	12,493	888	406	61,424	21,477	4,519	583	378	386	1,190	.251	.317	.391	.708
8	White Sox	.479	777	844	1,621	55,222	6,961	14,137	2,594	247	1,754	6,661	4,565	641	11,634	936	440	61,161	22,487	4,595	327	406	247	1,303	.256	.318	.407	.725
9	Diamondbacks	.480	778	842	1,620	55,397	7,202	14,127	2,975	417	1,661	6,857	5,265	450	13,131	992	389	62,024	22,919	5,053	508	404	452	1,133	.255	.323	.414	.736
10	Royals	.482	781	839	1,620	55,809	6,859	14,807	2,842	350	1,331	6,508	4,123	470	10,435	1,189	381	61,183	22,342	4,523	355	426	278	1,371	.265	.319	.400	.719
11	Reds	.485	785	835	1,620	55,031	6,973	13,857	2,713	266	1,724	6,640	5,142	575	12,353	1,040	422	61,871	22,274	4,703	705	418	430	1,089	.252	.320	.405	.725
12	Orioles	.485	786	833	1,619	55,751	7,206	14,389	2,778	167	1,995	6,905	4,501	480	11,971	590	262	61,372	23,486	4,940	242	398	261	1,303	.258	.317	.421	.738
13	Mets	.487	789	831	1,620	55,101	6,831	13,854	2,789	302	1,516	6,519	5,283	506	11,913	965	332	61,891	21,795	4,607	576	425	470	1,193	.251	.320	.396	.716
14	Athletics	.491	795	824	1,619	55,092	7,008	13,681	2,806	275	1,559	6,654	5,328	450	11,851	958	304	61,550	21,714	4,640	245	435	222	1,222	.248	.317	.394	.712
15	Brewers	.499	809	811	1,620	54,868	7,130	13,967	2,799	321	1,819	6,810	5,041	642	12,766	1,146	390	61,531	22,865	4,939	605	375	368	1,193	.255	.323	.417	.739
16	Phillies	.501	811	809	1,620	55,348	6,943	13,892	2,718	338	1,645	6,614	4,893	587	12,032	1,000	278	61,739	22,221	4,701	543	368	438	1,124	.251	.317	.401	.718
17	Braves	.503	814	805	1,619	54,986	6,782	13,972	2,757	238	1,431	6,456	5,386	474	12,060	737	320	61,877	21,498	4,426	662	369	465	1,312	.254	.324	.391	.715
18	Blue Jays	.503	815	805	1,620	55,313	7,504	14,054	2,901	210	2,013	7,160	5,294	501	11,679	850	296	61,857	23,414	5,124	303	446	238	1,318	.254	.322	.423	.746
19	Indians	.505	817	801	1,618	55,106	7,273	14,131	3,017	253	1,601	6,917	5,470	603	11,992	980	324	62,002	22,457	4,871	349	474	279	1,261	.256	.328	.408	.735
20	Cubs	.506	818	799	1,618	55,042	7,049	13,858	2,876	287	1,701	6,702	5,305	634	13,009	712	341	61,854	22,411	4,864	514	359	391	1,196	.252	.323	.407	.730
21	Nationals	.508	822	796	1,618	54,907	6,988	13,945	2,716	269	1,678	6,661	5,201	524	12,590	950	340	61,669	22,233	4,663	605	432	386	1,201	.254	.322	.405	.727
22	Giants	.513	831	789	1,620	55,324	6,626	14,254	2,834	389	1,235	6,269	4,654	438	11,313	815	355	61,446	21,571	4,458	560	470	417	1,285	.258	.318	.390	.708
23	Tigers	.513	831	788	1,619	55,915	7,555	15,102	2,869	344	1,747	7,239	5,115	475	11,675	659	312	62,251	23,900	4,960	317	429	376	1,389	.270	.334	.427	.762
24	Rays	.527	855	766	1,621	54,774	7,105	13,675	2,750	320	1,779	6,794	5,628	615	12,886	1,168	445	61,757	22,402	4,849	278	462	293	1,140	.250	.324	.409	.733
25	Rangers	.533	864	757	1,621	55,649	7,817	14,792	2,866	278	1,901	7,439	4,893	590	11,654	1,154	422	61,992	23,917	5,045	379	481	318	1,194	.266	.329	.430	.759