2017 MLB Relative Power Index (RPI),as of the games of May 21,2017 from ESPN.GO.COM

MLB RPI Rankings

RK	TEAM	RPI	W	L	PCT	SOS	PWR	RS	RA	EXPW-L	EXPWP
1	Colorado Rockies	.546	28	17	.622	.520	0	225	208	24-21	.539
2	New York Yankees	.544	25	16	.610	.522	0	232	177	26-15	.632
3	Houston Astros	.541	29	15	.659	.502	0	220	166	28-16	.637
4	Baltimore Orioles	.536	25	17	.595	.516	0	197	185	22-20	.531
5	Cleveland Indians	.528	23	19	.548	.522	0	184	168	23-19	.545
6	Chicago Cubs	.521	22	20	.524	.520	0	213	197	23-19	.539
7	Boston Red Sox	.520	22	21	.512	.522	0	196	188	22-21	.521
8	Minnesota Twins	.519	22	18	.550	.509	0	177	183	19-21	.483
9	Milwaukee Brewers	.515	25	19	.568	.497	0	233	206	25-19	.561
10	Detroit Tigers	.514	21	21	.500	.519	0	206	215	20-22	.479
11	Arizona Diamondbacks	.514	26	19	.578	.492	0	226	179	28-17	.615
12	St. Louis Cardinals	.510	22	19	.537	.501	0	186	169	22-19	.548
13	Los Angeles Dodgers	.509	26	19	.578	.486	0	228	164	30-15	.659
14	Tampa Bay Rays	.506	23	23	.500	.508	0	216	195	25-21	.551
15	Washington Nationals	.502	26	17	.605	.468	0	246	205	25-18	.590
16	Chicago White Sox	.498	20	22	.476	.506	0	193	171	24-18	.560
17	Texas Rangers	.498	24	21	.533	.486	0	215	190	25-20	.561
18	Los Angeles Angels	.497	23	23	.500	.496	0	192	199	22-24	.482
19	Cincinnati Reds	.496	20	23	.465	.507	0	218	221	21-22	.493
20	Oakland Athletics	.490	20	24	.455	.502	0	176	219	17-27	.392
21	Toronto Blue Jays	.489	19	26	.422	.511	0	186	202	21-24	.459
22	Pittsburgh Pirates	.489	20	24	.455	.500	0	167	199	18-26	.413
23	Kansas City Royals	.486	18	25	.419	.509	0	145	190	16-27	.368
24	San Francisco Giants	.485	19	26	.422	.506	0	154	217	15-30	.335
25	Seattle Mariners	.483	20	25	.444	.495	0	206	226	20-25	.454
26	San Diego Padres	.466	16	30	.348	.505	0	158	243	14-32	.297
27	Philadelphia Phillies	.459	15	26	.366	.490	0	183	202	18-23	.451
28	Atlanta Braves	.456	18	23	.439	.462	0	188	211	18-23	.443
29	New York Mets	.441	18	24	.429	.445	0	210	237	18-24	.440
30	Miami Marlins	.440	15	28	.349	.470	0	178	222	17-26	.391

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.