2015 MLB Relative Power Index (RPI),as of the games of April 29,2015 from ESPN.GO.COM

MLB RPI Rankings
RK	TEAM	RPI	W	L	PCT	SOS	PWR	RS	RA	EXPW-L	EXPWP
1	New York Yankees	.587	13	9	.591	.586	7	109	84	14-8	.627
2	Detroit Tigers	.563	15	7	.682	.523	4	107	90	13-9	.586
3	Chicago Cubs	.557	12	8	.600	.543	10	89	77	11-9	.572
4	New York Mets	.554	15	7	.682	.511	2	95	73	14-8	.629
5	Tampa Bay Rays	.539	12	10	.545	.536	14	87	86	11-11	.506
6	Kansas City Royals	.523	14	7	.667	.475	1	111	73	15-6	.698
7	San Diego Padres	.519	11	12	.478	.532	8	105	108	11-12	.486
8	Los Angeles Dodgers	.517	13	8	.619	.482	5	100	77	13-8	.628
9	Minnesota Twins	.514	9	12	.429	.543	27	74	98	8-13	.363
10	Baltimore Orioles	.510	10	10	.500	.514	17	112	104	11-9	.537
11	Houston Astros	.509	14	7	.667	.457	12	100	73	14-7	.652
12	Pittsburgh Pirates	.508	12	10	.545	.495	9	89	71	13-9	.611
13	Toronto Blue Jays	.506	10	12	.455	.523	11	117	114	11-11	.513
14	Boston Red Sox	.506	12	10	.545	.492	6	113	119	10-12	.474
15	St. Louis Cardinals	.505	14	6	.700	.440	3	83	52	14-6	.718
16	Chicago White Sox	.503	8	10	.444	.522	26	62	77	7-11	.393
17	Atlanta Braves	.497	10	11	.476	.504	19	93	98	10-11	.474
18	Miami Marlins	.494	10	12	.455	.507	23	97	87	12-10	.554
19	Colorado Rockies	.493	11	10	.524	.482	13	88	105	9-12	.413
20	Cleveland Indians	.488	7	13	.350	.534	25	78	93	8-12	.413
21	San Francisco Giants	.480	9	13	.409	.503	22	66	94	7-15	.330
22	Arizona Diamondbacks	.477	10	11	.476	.478	24	96	86	12-9	.555
23	Cincinnati Reds	.475	10	11	.476	.474	20	84	94	9-12	.444
24	Seattle Mariners	.471	10	11	.476	.469	21	77	93	9-12	.407
25	Oakland Athletics	.471	9	13	.409	.491	18	105	93	12-10	.560
26	Washington Nationals	.466	9	13	.409	.485	16	95	105	10-12	.450
27	Los Angeles Angels	.462	10	11	.476	.458	15	83	83	11-11	.500
28	Philadelphia Phillies	.455	8	14	.364	.485	29	60	100	6-16	.265
29	Milwaukee Brewers	.416	5	17	.227	.478	30	71	118	6-16	.266
30	Texas Rangers	.413	7	14	.333	.439	28	75	96	8-13	.379

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.