The Washington Nationals had the worst winning percentage by a team in 2009, winning 36.4 percent of the time.

	TEAM	W%	SEASON	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	Nationals	.364	2009	59	103	162	5,493	710	1,416	271	38	156	685	617	56	1,208	73	40	6,272	2,231	465	64	42	39	133	.258	.337	.406	.743
2	Pirates	.385	2009	62	99	161	5,417	636	1,364	289	34	125	612	499	46	1,142	90	32	6,058	2,096	448	60	36	44	124	.252	.318	.387	.705
3	Orioles	.395	2009	64	98	162	5,618	741	1,508	307	19	160	708	517	39	1,013	76	37	6,233	2,333	486	13	46	25	131	.268	.332	.415	.747
4	Indians	.401	2009	65	97	162	5,568	773	1,468	314	28	161	730	582	81	1,211	84	31	6,320	2,321	503	39	50	20	140	.264	.339	.417	.756
5	Royals	.401	2009	65	97	162	5,532	686	1,432	276	51	144	657	457	42	1,091	88	29	6,101	2,242	471	38	32	20	135	.259	.318	.405	.724
6	Mets	.432	2009	70	92	162	5,453	671	1,472	295	49	95	631	526	36	928	122	44	6,158	2,150	439	88	55	49	144	.270	.335	.394	.729
7	Diamondbacks	.432	2009	70	92	162	5,565	720	1,408	307	45	173	686	571	37	1,298	102	40	6,268	2,324	525	54	41	47	93	.253	.324	.418	.742
8	Astros	.457	2009	74	88	162	5,436	643	1,415	270	32	142	616	448	43	990	113	44	6,038	2,175	444	66	45	37	153	.260	.319	.400	.719
9	Athletics	.463	2009	75	87	162	5,584	759	1,464	307	21	135	723	527	50	1,046	133	48	6,246	2,218	463	31	54	16	130	.262	.328	.397	.726
10	Padres	.463	2009	75	87	162	5,425	638	1,315	265	31	141	605	586	57	1,182	82	29	6,178	2,065	437	74	36	52	131	.242	.321	.381	.701
11	Blue Jays	.463	2009	75	87	162	5,696	798	1,516	339	13	209	766	548	45	1,028	73	23	6,362	2,508	561	24	49	23	130	.266	.333	.440	.773
12	Reds	.481	2009	78	84	162	5,462	673	1,349	280	25	158	637	531	53	1,129	96	40	6,187	2,153	463	100	41	37	103	.247	.318	.394	.712
13	White Sox	.488	2009	79	83	162	5,463	724	1,410	246	20	184	695	534	62	1,022	113	49	6,132	2,248	450	34	39	25	139	.258	.329	.411	.740
14	Brewers	.494	2009	80	82	162	5,510	785	1,447	281	37	182	757	610	71	1,231	68	37	6,296	2,348	500	58	47	44	128	.263	.341	.426	.767
15	Cubs	.516	2009	83	78	161	5,486	707	1,398	293	29	161	678	592	59	1,185	56	34	6,244	2,232	483	65	42	44	134	.255	.332	.407	.738
16	Rays	.519	2009	84	78	162	5,462	803	1,434	297	36	199	765	642	49	1,229	194	61	6,223	2,400	532	25	45	36	104	.263	.343	.439	.782
17	Mariners	.525	2009	85	77	162	5,543	640	1,430	280	19	160	613	421	49	1,093	89	33	6,113	2,228	459	56	44	39	124	.258	.314	.402	.716
18	Tigers	.528	2009	86	77	163	5,540	743	1,443	245	35	183	718	540	61	1,114	72	33	6,233	2,307	463	53	39	30	131	.260	.331	.416	.747
19	Braves	.531	2009	86	76	162	5,539	735	1,459	300	20	149	700	602	52	1,064	58	26	6,335	2,246	469	95	47	54	142	.263	.339	.405	.744
20	Twins	.534	2009	87	76	163	5,608	817	1,539	271	40	172	770	585	45	1,021	85	32	6,346	2,406	483	51	57	46	147	.274	.345	.429	.774
21	Rangers	.537	2009	87	75	162	5,526	784	1,436	296	27	224	748	472	37	1,253	149	36	6,126	2,458	547	40	51	23	97	.260	.320	.445	.764
22	Marlins	.537	2009	87	75	162	5,572	772	1,493	296	25	159	727	568	63	1,226	75	35	6,312	2,316	480	70	39	46	110	.268	.340	.416	.756
23	Giants	.543	2009	88	74	162	5,493	657	1,411	275	43	122	612	392	50	1,158	78	28	6,057	2,138	440	67	55	41	115	.257	.309	.389	.699
24	Cardinals	.562	2009	91	71	162	5,465	730	1,436	294	29	160	694	528	61	1,041	75	31	6,165	2,268	483	68	43	73	127	.263	.332	.415	.747
25	Rockies	.568	2009	92	70	162	5,398	804	1,408	300	50	190	760	660	47	1,277	106	55	6,241	2,378	540	76	60	40	111	.261	.343	.441	.784