2017 MLB Relative Power Index (RPI),as of the games of September 2,2017 from ESPN.GO.COM

MLB RPI Rankings
RK	TEAM	RPI	W	L	PCT	SOS	PWR	RS	RA	EXPW-L	EXPWP
1	Los Angeles Dodgers	.543	92	43	.681	.496	0	664	460	91-44	.676
2	Houston Astros	.527	82	53	.607	.501	0	751	591	83-52	.618
3	Arizona Diamondbacks	.522	78	58	.574	.505	0	670	550	81-55	.597
4	Cleveland Indians	.521	79	56	.585	.499	0	669	500	87-48	.642
5	Washington Nationals	.518	82	53	.607	.488	0	707	560	83-52	.614
6	Boston Red Sox	.517	77	59	.566	.500	0	647	559	78-58	.573
7	New York Yankees	.511	72	63	.533	.504	0	695	565	81-54	.602
8	Chicago Cubs	.510	75	60	.556	.495	0	691	593	78-57	.576
9	Colorado Rockies	.509	72	63	.533	.501	0	688	648	72-63	.530
10	Minnesota Twins	.507	71	64	.526	.500	0	669	668	68-67	.501
11	Baltimore Orioles	.507	69	67	.507	.506	0	663	687	66-70	.482
12	Los Angeles Angels	.506	70	66	.515	.504	0	600	590	69-67	.508
13	Milwaukee Brewers	.504	71	65	.522	.497	0	613	598	70-66	.512
14	Tampa Bay Rays	.501	68	69	.496	.502	0	592	592	69-69	.500
15	Texas Rangers	.501	67	68	.496	.502	0	686	654	71-64	.524
16	St. Louis Cardinals	.500	68	67	.504	.499	0	643	589	73-62	.544
17	Kansas City Royals	.499	66	68	.493	.502	0	576	648	59-75	.441
18	Seattle Mariners	.499	68	68	.500	.498	0	630	657	65-71	.479
19	Toronto Blue Jays	.494	63	73	.463	.505	0	578	673	58-78	.424
20	Miami Marlins	.492	67	68	.496	.490	0	633	658	65-70	.481
21	Pittsburgh Pirates	.490	64	72	.471	.496	0	568	636	60-76	.444
22	San Diego Padres	.489	61	75	.449	.503	0	522	667	52-84	.380
23	Detroit Tigers	.486	58	77	.430	.505	0	632	715	59-76	.439
24	Oakland Athletics	.485	58	77	.430	.503	0	595	704	56-79	.417
25	Cincinnati Reds	.484	58	78	.426	.503	0	650	746	59-77	.432
26	New York Mets	.481	58	77	.430	.498	0	616	700	59-76	.436
27	Atlanta Braves	.479	59	75	.440	.491	0	614	687	60-74	.444
28	Chicago White Sox	.478	53	81	.396	.506	0	573	685	55-79	.412
29	San Francisco Giants	.474	54	84	.391	.502	0	540	673	54-84	.392
30	Philadelphia Phillies	.466	51	84	.378	.496	0	553	675	54-81	.402

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.