2015 MLB Relative Power Index (RPI),as of the games of May 19,2015

MLB RPI Rankings
RK	TEAM	RPI	W	L	PCT	SOS	PWR	RS	RA	EXPW-L	EXPWP
1	Detroit Tigers	.554	23	17	.575	.547	4	173	161	21-19	.536
2	Kansas City Royals	.544	25	14	.641	.512	3	195	137	26-13	.670
3	St. Louis Cardinals	.543	26	13	.667	.502	1	172	120	26-13	.673
4	New York Yankees	.532	22	18	.550	.526	8	177	164	22-18	.538
5	Minnesota Twins	.526	22	17	.564	.514	14	179	174	20-19	.514
6	New York Mets	.516	23	17	.575	.497	9	153	133	23-17	.570
7	Washington Nationals	.516	23	17	.575	.497	6	202	175	23-17	.571
8	Los Angeles Dodgers	.516	24	14	.632	.477	2	186	130	26-12	.672
9	Chicago Cubs	.513	21	17	.553	.500	7	163	164	19-19	.497
10	Houston Astros	.512	26	14	.650	.466	5	176	152	23-17	.573
11	San Diego Padres	.511	20	20	.500	.514	11	179	193	18-22	.462
12	Tampa Bay Rays	.507	22	18	.550	.493	12	161	142	22-18	.562
13	San Francisco Giants	.507	21	18	.538	.496	13	147	145	20-19	.507
14	Chicago White Sox	.505	18	18	.500	.506	23	135	165	14-22	.401
15	Cleveland Indians	.497	15	23	.395	.532	25	163	182	17-21	.445
16	Cincinnati Reds	.493	18	21	.462	.504	15	153	174	17-22	.436
17	Pittsburgh Pirates	.492	18	21	.462	.503	16	151	141	21-18	.534
18	Los Angeles Angels	.491	20	19	.513	.484	10	143	141	20-19	.507
19	Baltimore Orioles	.490	17	19	.472	.496	20	165	159	19-17	.519
20	Toronto Blue Jays	.488	18	23	.439	.504	18	212	199	22-19	.532
21	Arizona Diamondbacks	.485	17	21	.447	.497	26	176	169	20-18	.520
22	Boston Red Sox	.483	19	20	.487	.481	17	155	187	16-23	.407
23	Seattle Mariners	.482	17	21	.447	.493	19	144	161	17-21	.444
24	Atlanta Braves	.479	18	20	.474	.481	22	162	167	18-20	.485
25	Milwaukee Brewers	.478	15	25	.375	.512	28	153	201	15-25	.367
26	Philadelphia Phillies	.474	17	24	.415	.493	29	129	183	14-27	.332
27	Miami Marlins	.472	16	24	.400	.496	21	155	166	19-21	.466
28	Colorado Rockies	.471	14	22	.389	.499	30	141	188	13-23	.360
29	Texas Rangers	.466	16	23	.410	.485	24	161	182	17-22	.439
30	Oakland Athletics	.459	14	27	.341	.498	27	184	190	20-21	.484

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.