Between the 2005 and 2014 seasons, the Kansas City Royals had the lowest winning percentage by a team, winning 44.0 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	.440	712	908	1,620	55,772	6,922	14,831	2,942	368	1,204	6,550	4,294	519	10,189	1,069	392	61,443	22,121	4,514	405	453	297	1,364	.266	.322	.397	.718
2	Astros	.440	712	907	1,620	54,836	6,554	13,801	2,708	259	1,471	6,225	4,710	539	11,728	1,041	422	61,114	21,440	4,438	645	384	340	1,236	.252	.315	.391	.706
3	Pirates	.445	721	898	1,619	54,986	6,630	13,911	2,845	305	1,426	6,355	4,751	621	12,051	822	363	61,395	21,644	4,576	615	422	380	1,235	.253	.317	.394	.711
4	Mariners	.458	742	878	1,620	55,379	6,506	13,973	2,621	251	1,422	6,158	4,382	457	11,112	984	358	60,970	21,362	4,294	373	379	355	1,168	.252	.310	.386	.696
5	Orioles	.466	754	865	1,619	55,884	7,259	14,714	2,888	206	1,788	6,941	4,644	509	10,623	843	322	61,773	23,378	4,882	313	423	304	1,348	.263	.323	.418	.742
6	Cubs	.467	756	862	1,618	55,366	6,901	14,238	2,971	295	1,619	6,555	4,774	515	11,653	761	360	61,614	22,656	4,885	593	366	366	1,247	.257	.320	.409	.729
7	Rockies	.468	759	862	1,621	55,612	7,688	14,911	2,968	425	1,675	7,310	5,336	500	12,022	1,011	408	62,667	23,754	5,068	785	434	433	1,193	.268	.335	.427	.762
8	Marlins	.471	763	856	1,619	55,165	6,918	14,091	2,855	338	1,533	6,565	5,114	587	12,594	934	351	61,952	22,221	4,726	677	409	464	1,174	.255	.323	.403	.726
9	Nationals	.477	772	846	1,618	54,877	6,761	13,921	2,814	281	1,487	6,421	5,193	596	12,041	901	378	61,763	21,758	4,582	689	408	402	1,245	.254	.323	.396	.719
10	Diamondbacks	.481	780	840	1,620	55,151	7,099	14,024	2,995	379	1,619	6,792	5,376	492	12,106	872	364	62,024	22,634	4,993	567	438	461	1,165	.254	.324	.410	.734
11	Padres	.486	787	834	1,621	54,767	6,493	13,503	2,643	331	1,356	6,158	5,338	493	12,095	1,053	353	61,658	20,876	4,330	633	427	418	1,150	.247	.317	.381	.698
12	Twins	.488	792	830	1,622	55,685	7,283	14,704	2,834	329	1,333	6,882	5,182	472	10,532	948	363	62,186	22,195	4,496	366	481	376	1,379	.264	.329	.399	.728
13	Indians	.498	807	813	1,620	55,504	7,480	14,454	3,066	250	1,644	7,147	5,451	653	11,935	861	342	62,428	22,952	4,960	349	471	330	1,234	.260	.331	.414	.745
14	Blue Jays	.498	807	813	1,620	55,539	7,498	14,401	3,047	260	1,838	7,151	5,083	540	10,744	849	315	61,913	23,482	5,145	286	465	279	1,291	.259	.325	.423	.748
15	Reds	.500	810	810	1,621	55,176	7,216	14,050	2,849	218	1,817	6,883	5,390	596	12,093	940	381	62,309	22,786	4,884	732	415	459	1,110	.255	.325	.413	.738
16	Mets	.500	810	810	1,620	55,273	7,102	14,215	2,864	338	1,449	6,747	5,331	483	11,157	1,313	387	62,244	22,102	4,651	699	458	530	1,153	.257	.325	.400	.725
17	White Sox	.504	817	804	1,621	55,253	7,249	14,293	2,594	213	1,890	6,959	4,774	636	10,928	1,028	491	61,467	22,983	4,697	371	433	285	1,310	.259	.322	.416	.738
18	Giants	.505	818	801	1,619	55,115	6,654	14,201	2,839	383	1,263	6,288	4,615	452	10,542	815	342	61,314	21,595	4,485	680	452	483	1,312	.258	.318	.392	.710
19	Rays	.506	821	800	1,621	54,949	7,316	14,033	2,805	333	1,702	6,981	5,596	576	11,976	1,349	478	61,934	22,610	4,840	328	485	297	1,169	.255	.328	.411	.739
20	Brewers	.507	821	799	1,620	55,026	7,329	14,195	2,947	322	1,842	7,008	5,017	742	11,885	999	367	61,838	23,312	5,111	639	414	428	1,198	.258	.326	.424	.750
21	Rangers	.516	837	784	1,621	56,113	8,018	15,160	3,041	290	1,899	7,631	4,913	507	11,105	1,049	367	62,380	24,478	5,230	375	472	327	1,271	.270	.332	.436	.768
22	Athletics	.519	840	779	1,619	55,232	7,206	13,915	2,825	251	1,511	6,836	5,697	485	11,010	917	292	62,156	21,775	4,587	267	475	246	1,287	.252	.325	.394	.719
23	Dodgers	.527	854	765	1,619	55,124	7,035	14,491	2,775	317	1,338	6,689	5,310	526	10,836	1,103	437	62,079	21,914	4,430	679	440	512	1,301	.263	.331	.398	.729
24	Braves	.531	860	760	1,620	55,226	7,256	14,265	2,870	257	1,626	6,919	5,533	451	11,931	724	319	62,281	22,527	4,753	680	391	456	1,296	.258	.329	.408	.737
25	Tigers	.531	861	760	1,621	56,229	7,813	15,397	2,968	365	1,746	7,481	4,952	483	11,025	682	296	62,512	24,333	5,079	386	462	383	1,359	.274	.335	.433	.768