Between the 1999 and 2008 seasons, the Kansas City Royals had the worst winning percentage by a team, winning 41.4 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	Royals	.414	671	948	1,619	55,851	7,612	15,018	2,913	371	1,377	7,154	4,631	625	9,696	950	420	62,063	22,804	4,661	456	500	291	1,357	.269	.329	.408	.737
2	Rays	.420	679	938	1,617	55,516	7,274	14,563	2,840	337	1,557	6,920	4,927	575	10,913	1,212	475	61,835	22,748	4,734	364	453	293	1,198	.262	.326	.410	.736
3	Pirates	.431	697	920	1,617	55,231	7,129	14,300	2,877	307	1,528	6,782	4,952	739	11,025	792	385	62,036	22,375	4,712	676	438	409	1,208	.259	.326	.405	.731
4	Tigers	.440	712	906	1,618	55,799	7,540	14,858	2,859	441	1,754	7,179	4,670	535	10,582	865	455	61,880	23,861	5,054	413	463	264	1,248	.266	.326	.428	.754
5	Orioles	.440	712	906	1,620	55,901	7,619	14,985	2,990	243	1,676	7,246	5,052	578	9,332	1,095	437	62,406	23,489	4,909	388	487	319	1,332	.268	.332	.420	.753
6	Nationals	.445	720	899	1,619	54,795	6,906	14,101	3,031	309	1,450	6,553	5,128	546	10,546	874	464	61,649	22,100	4,790	787	393	525	1,325	.257	.325	.403	.728
7	Brewers	.454	735	883	1,619	55,049	7,277	14,084	2,961	281	1,805	6,960	5,437	682	12,102	904	383	62,246	23,022	5,047	648	430	469	1,239	.256	.328	.418	.746
8	Rockies	.462	749	872	1,621	56,026	8,421	15,516	3,121	411	1,787	7,979	5,566	547	10,727	934	431	63,387	24,820	5,319	791	457	469	1,275	.277	.346	.443	.789
9	Padres	.474	768	853	1,621	55,313	7,152	14,187	2,765	313	1,490	6,800	5,828	456	11,233	946	388	62,567	22,048	4,568	505	465	397	1,269	.256	.330	.399	.728
10	Reds	.474	769	852	1,623	55,516	7,634	14,379	2,929	239	1,960	7,290	5,623	637	11,874	1,018	391	62,841	23,666	5,128	662	403	477	1,199	.259	.332	.426	.758
11	Rangers	.484	784	836	1,620	56,539	8,629	15,506	3,203	307	2,161	8,245	5,379	548	10,762	762	317	63,282	25,806	5,671	324	492	349	1,291	.274	.340	.456	.797
12	Marlins	.487	788	830	1,618	55,231	7,367	14,560	2,969	351	1,624	6,979	5,171	654	11,420	1,159	489	62,161	23,103	4,944	643	462	474	1,180	.264	.331	.418	.750
13	Cubs	.489	791	828	1,619	55,510	7,533	14,620	2,927	290	1,868	7,182	5,296	474	10,962	781	352	62,484	23,731	5,085	773	431	467	1,265	.263	.330	.428	.758
14	Blue Jays	.503	814	805	1,619	55,971	7,988	15,064	3,206	298	1,799	7,627	5,209	682	10,346	804	328	62,608	24,263	5,303	257	489	318	1,354	.269	.336	.433	.770
15	Mariners	.513	831	789	1,620	56,105	7,920	15,276	2,848	287	1,617	7,508	5,382	521	9,918	1,160	426	62,925	23,549	4,752	415	502	446	1,262	.272	.339	.420	.759
16	Phillies	.515	834	785	1,619	55,741	7,999	14,714	3,047	357	1,825	7,603	6,221	607	11,314	1,138	307	63,652	23,950	5,229	639	444	600	1,173	.264	.342	.430	.772
17	Diamondbacks	.515	835	785	1,620	55,404	7,570	14,495	2,962	403	1,736	7,241	5,554	522	10,573	836	340	62,604	23,471	5,101	629	495	506	1,200	.262	.332	.424	.756
18	Twins	.519	839	779	1,619	55,859	7,590	15,140	3,029	373	1,404	7,152	5,064	524	9,848	1,060	482	62,304	23,127	4,806	354	503	393	1,417	.271	.335	.414	.749
19	Mets	.520	842	777	1,619	55,160	7,477	14,385	2,810	256	1,719	7,093	5,625	539	10,482	1,183	408	62,468	22,864	4,785	703	441	543	1,262	.261	.333	.415	.747
20	Dodgers	.521	844	776	1,620	55,276	7,337	14,454	2,692	305	1,654	7,004	5,348	548	10,141	1,078	443	62,243	22,718	4,651	649	422	453	1,283	.261	.330	.411	.741
21	Indians	.523	848	772	1,620	55,963	8,428	15,211	3,141	286	1,928	8,058	5,828	662	11,015	837	407	63,377	24,708	5,355	420	504	376	1,308	.272	.345	.442	.786
22	White Sox	.527	853	767	1,621	55,457	8,178	14,877	2,888	242	2,132	7,850	5,192	561	9,889	957	456	62,164	24,645	5,262	473	481	276	1,303	.268	.334	.444	.779
23	Giants	.528	853	764	1,618	55,208	7,702	14,644	2,984	351	1,726	7,336	5,853	527	9,708	771	357	62,811	23,508	5,061	758	465	735	1,340	.265	.339	.426	.765
24	Astros	.528	855	764	1,620	55,176	7,828	14,571	2,921	297	1,839	7,473	5,780	677	10,733	943	428	62,850	23,603	5,057	746	471	500	1,302	.264	.339	.428	.766
25	Angels	.539	873	747	1,620	55,840	7,803	15,227	2,898	291	1,604	7,413	4,922	533	9,264	1,246	524	62,222	23,519	4,793	427	500	435	1,260	.273	.335	.421	.756