2017 MLB Relative Power Index (RPI),as of the games of May 9,2017 from ESPN.GO.COM

MLB RPI Rankings

RK	TEAM	RPI	W	L	PCT	SOS	PWR	RS	RA	EXPW-L	EXPWP
1	Baltimore Orioles	.586	22	10	.688	.552	0	143	129	18-14	.551
2	New York Yankees	.573	21	10	.677	.538	0	180	124	21-10	.678
3	Boston Red Sox	.547	17	15	.531	.553	0	145	132	17-15	.547
4	Washington Nationals	.536	21	12	.636	.502	0	202	152	21-12	.638
5	Houston Astros	.534	22	11	.667	.490	0	161	123	21-12	.631
6	Colorado Rockies	.526	21	13	.618	.495	0	163	157	18-16	.519
7	St. Louis Cardinals	.525	18	14	.563	.512	0	146	135	17-15	.539
8	Chicago Cubs	.521	17	16	.515	.522	0	166	155	18-15	.534
9	Cincinnati Reds	.520	18	15	.545	.512	0	172	154	18-15	.555
10	Milwaukee Brewers	.519	17	16	.515	.520	0	166	154	18-15	.537
11	Detroit Tigers	.518	16	15	.516	.518	0	157	158	15-16	.497
12	Cleveland Indians	.514	18	14	.563	.497	0	136	123	18-14	.550
13	Chicago White Sox	.514	15	16	.484	.523	0	123	119	16-15	.517
14	Arizona Diamondbacks	.501	18	16	.529	.491	0	162	145	19-15	.555
15	Minnesota Twins	.500	16	14	.533	.488	0	140	143	15-15	.489
16	Seattle Mariners	.496	16	17	.485	.499	0	165	155	18-15	.531
17	Los Angeles Dodgers	.494	19	14	.576	.467	0	163	113	22-11	.675
18	Tampa Bay Rays	.493	16	19	.457	.505	0	149	148	18-17	.503
19	Philadelphia Phillies	.490	13	18	.419	.514	0	146	145	16-15	.503
20	Pittsburgh Pirates	.490	14	19	.424	.512	0	121	151	13-20	.391
21	Toronto Blue Jays	.487	12	21	.364	.529	0	122	149	13-20	.401
22	Los Angeles Angels	.485	17	18	.486	.484	0	135	152	15-20	.441
23	Oakland Athletics	.474	15	18	.455	.480	0	126	165	12-21	.368
24	Texas Rangers	.462	14	20	.412	.479	0	154	152	17-17	.507
25	Miami Marlins	.458	13	19	.406	.475	0	144	155	15-17	.463
26	New York Mets	.449	16	16	.500	.432	0	162	168	15-17	.482
27	Atlanta Braves	.449	11	19	.367	.476	0	133	166	12-18	.391
28	San Francisco Giants	.448	11	23	.324	.490	0	109	178	9-25	.273
29	Kansas City Royals	.447	12	20	.375	.471	0	96	130	11-21	.353
30	San Diego Padres	.445	13	21	.382	.466	0	122	179	11-23	.317

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.