The Pittsburgh Pirates have averaged a win percentage of .500 all-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	Alleghenys	.500	1882	39	39	79	2,889	426	725	106	59	18		92		183			2,981	1,003	183					.251		.347
2	Alleghenys	.316	1883	31	67	98	3,607	525	892	120	58	13		164		345			3,771	1,167	191					.247		.324
3	Alleghenys	.278	1884	30	78	110	3,689	406	777	105	50	2		143	41	411			3,873	988	157					.211	.248	.268	.516
4	Alleghenys	.505	1885	56	55	111	3,975	547	955	123	79	5	371	189	44	537			4,208	1,251	207					.240	.282	.315	.597
5	Alleghenys	.584	1886	80	57	140	4,854	810	1,171	186	96	16	563	478	38	713	260		5,370	1,597	298					.241	.314	.329	.643
6	Alleghenys	.444	1887	55	69	125	4,414	621	1,141	183	78	20	479	319	38	381	221		4,771	1,540	281					.258	.314	.349	.663
7	Alleghenys	.493	1888	66	68	139	4,713	534	1,070	150	49	14	390	194	46	583	287		4,953	1,360	213					.227	.264	.289	.553
8	Alleghenys	.462	1889	61	71	134	4,748	726	1,202	209	65	42	597	420	44	467	231		5,212	1,667	316					.253	.320	.351	.671
9	Alleghenys	.169	1890	23	113	138	4,739	597	1,088	160	43	20	426	408	66	460	208		5,213	1,394	223					.230	.300	.294	.594
10	Pirates	.407	1891	55	80	137	4,794	679	1,148	148	71	29	524	427	50	503	205		5,271	1,525	248					.239	.308	.318	.626
11	Pirates	.523	1892	80	73	155	5,469	802	1,288	143	108	38	600	435	44	453	222		5,948	1,761	289					.236	.297	.322	.619
12	Pirates	.628	1893	81	48	131	4,834	970	1,447	176	127	37	816	537	62	274	210		5,433	1,988	340					.299	.377	.411	.788
13	Pirates	.500	1894	65	65	133	4,700	965	1,465	223	125	48	812	444	68	210	257		5,375	2,082	396	163				.312	.379	.443	.822
14	Pirates	.538	1895	71	61	135	4,677	815	1,355	192	89	27	677	378	65	299	257		5,226	1,806	308	106				.290	.351	.386	.737
15	Pirates	.512	1896	66	63	131	4,701	787	1,371	169	94	27	667	387	58	286	217		5,254	1,809	290	108				.292	.353	.385	.738
16	Pirates	.458	1897	60	71	135	4,590	676	1,266	140	108	25	575	359	67	333	170		5,114	1,697	273	98				.276	.337	.370	.707
17	Pirates	.486	1898	72	76	152	5,087	634	1,313	140	88	14	520	336	74	339	107		5,638	1,671	242	141				.258	.313	.328	.642
18	Pirates	.510	1899	76	73	155	5,486	841	1,582	196	121	29	706	386	63	344	179		6,079	2,107	346	144				.288	.342	.384	.726
19	Pirates	.568	1900	79	60	140	4,817	733	1,312	185	100	26	602	327	63	319	174		5,317	1,775	311	110				.272	.327	.368	.695
20	Pirates	.647	1901	90	49	140	4,913	777	1,407	182	92	29	636	386	52	497	203		5,468	1,860	303	117				.286	.345	.379	.723
21	Pirates	.741	1902	103	36	142	4,926	774	1,410	189	95	18	660	372	64	440	222		5,480	1,843	302	118				.286	.344	.374	.718
22	Pirates	.650	1903	91	49	141	4,988	793	1,429	208	110	34	650	364	50	400	172		5,511	1,959	352	109				.286	.341	.393	.734
23	Pirates	.569	1904	87	66	156	5,160	675	1,333	164	102	15	523	391	47	516	178		5,714	1,746	281	116				.258	.316	.338	.655
24	Pirates	.627	1905	96	57	155	5,213	692	1,385	190	91	22	564	382	36	512	202		5,790	1,823	303	159				.266	.320	.350	.670
25	Pirates	.608	1906	93	60	154	5,030	622	1,313	164	67	12	497	424	42	385	162		5,686	1,647	243	190				.261	.324	.327	.651
	Total	.500		10,890	10,889	21,919	750,731	97,443	197,533	32,463	8,944	12,303	86,941	64,537	5,550	100,230	15,723	3,285	836,639	284,793	53,710	12,565	3,133	3,706	10,102	.263	.325	.379	.704