2015 MLB Relative Power Index (RPI),as of the games of May 30,2015

MLB RPI Rankings
RK	TEAM	RPI	W	L	PCT	SOS	PWR	RS	RA	EXPW-L	EXPWP
1	Kansas City Royals	.546	29	18	.617	.522	1	223	173	29-18	.624
2	St. Louis Cardinals	.540	32	17	.653	.502	2	206	148	32-17	.660
3	Detroit Tigers	.539	28	23	.549	.536	4	212	211	26-25	.502
4	Minnesota Twins	.532	29	19	.604	.508	10	219	199	26-22	.548
5	Houston Astros	.526	31	19	.620	.495	5	219	191	28-22	.568
6	Los Angeles Dodgers	.525	29	19	.604	.498	6	214	160	31-17	.641
7	San Francisco Giants	.518	30	21	.588	.495	7	209	195	27-24	.535
8	San Diego Padres	.513	24	27	.471	.527	17	218	232	24-27	.469
9	Chicago Cubs	.511	25	22	.532	.504	9	193	196	23-24	.492
10	Cleveland Indians	.510	23	26	.469	.524	18	219	218	25-24	.502
11	Los Angeles Angels	.508	26	24	.520	.503	11	197	191	26-24	.515
12	New York Yankees	.507	26	24	.520	.503	13	228	215	26-24	.529
13	Washington Nationals	.503	28	21	.571	.480	3	226	204	27-22	.551
14	Arizona Diamondbacks	.501	23	25	.479	.508	22	227	213	26-22	.532
15	Pittsburgh Pirates	.500	26	23	.531	.490	15	207	167	30-19	.606
16	Seattle Mariners	.499	24	25	.490	.502	16	183	198	23-26	.461
17	New York Mets	.498	27	23	.540	.484	12	188	183	26-24	.513
18	Texas Rangers	.497	25	25	.500	.496	23	229	231	25-25	.496
19	Chicago White Sox	.496	22	26	.458	.509	21	173	221	18-30	.380
20	Colorado Rockies	.486	21	26	.447	.499	28	203	234	20-27	.429
21	Cincinnati Reds	.485	21	27	.438	.501	25	183	214	20-28	.422
22	Tampa Bay Rays	.485	25	25	.500	.480	8	183	174	26-24	.525
23	Toronto Blue Jays	.484	23	28	.451	.495	24	263	237	28-23	.552
24	Baltimore Orioles	.483	23	25	.479	.484	14	202	199	24-24	.507
25	Oakland Athletics	.478	19	33	.365	.516	29	219	221	26-26	.495
26	Atlanta Braves	.476	24	25	.490	.471	19	195	210	23-26	.463
27	Boston Red Sox	.472	22	28	.440	.483	20	192	239	20-30	.392
28	Miami Marlins	.469	20	30	.400	.492	30	191	211	23-27	.450
29	Milwaukee Brewers	.461	16	34	.320	.508	27	186	252	18-32	.353
30	Philadelphia Phillies	.459	19	32	.373	.487	26	156	226	16-35	.323

Glossary

• W: Wins
• L: Losses
• PCT: Winning percentage
• RPI: Relative Power Index+
• SOS: Strength of schedule

• PWR: ESPN Power Ranking
• RS: Runs scored
• RA: Runs allowed
• EXW-L: Expected W-L*
• EXWP: Expected winning percentage*

+The basic formula is 25% team winning percentage, 50% opponents' average winning percentage, and 25% opponents' opponents' average winning percentage.
*ExW-L and ExWP are derived from Bill James' Pythagorean theorem of baseball: Runs scored [squared] / (Runs scored [squared] + runs allowed [squared]). This formula was designed to relate a team's runs scored and runs allowed to its won-lost record.