2015 MLB Relative Power Index (RPI),as of the games of April 15,2015

MLB RPI Rankings
RK	TEAM	RPI	W	L	PCT	SOS	PWR	RS	RA	EXPW-L	EXPWP
1	Chicago Cubs	.671	5	3	.625	.687	22	32	27	5-3	.584
2	Kansas City Royals	.609	7	1	.875	.520	2	53	21	7-1	.864
3	Detroit Tigers	.589	8	1	.889	.489	1	54	21	8-1	.869
4	Colorado Rockies	.581	7	2	.778	.516	11	45	25	7-2	.764
5	Atlanta Braves	.560	6	3	.667	.525	14	36	29	5-4	.606
6	Cincinnati Reds	.556	5	4	.556	.557	7	33	37	4-5	.443
7	St. Louis Cardinals	.550	4	3	.571	.543	4	26	20	4-3	.628
8	Los Angeles Dodgers	.547	6	3	.667	.507	8	43	40	5-4	.536
9	New York Mets	.542	6	3	.667	.500	18	34	25	6-3	.649
10	San Diego Padres	.524	6	4	.600	.499	16	43	34	6-4	.615
11	Tampa Bay Rays	.523	5	4	.556	.512	28	40	42	4-5	.476
12	Toronto Blue Jays	.519	5	4	.556	.506	5	53	39	6-3	.649
13	Baltimore Orioles	.519	5	4	.556	.506	6	47	46	5-4	.511
14	Miami Marlins	.514	3	6	.333	.574	23	34	42	4-5	.396
15	Minnesota Twins	.498	2	6	.250	.581	30	19	46	1-7	.146
16	Arizona Diamondbacks	.498	4	5	.444	.516	21	38	38	5-5	.500
17	Cleveland Indians	.489	3	5	.375	.527	17	27	34	3-5	.387
18	Los Angeles Angels	.487	4	5	.444	.501	10	34	39	4-5	.432
19	San Francisco Giants	.473	3	7	.300	.530	15	26	40	3-7	.297
20	New York Yankees	.472	3	6	.333	.519	26	45	49	4-5	.458
21	Chicago White Sox	.468	3	5	.375	.498	24	24	38	2-6	.285
22	Boston Red Sox	.463	6	3	.667	.395	3	56	50	5-4	.556
23	Pittsburgh Pirates	.459	3	6	.333	.501	19	29	30	4-5	.483
24	Philadelphia Phillies	.444	3	6	.333	.481	20	22	37	2-7	.261
25	Washington Nationals	.444	3	6	.333	.481	9	34	42	4-5	.396
26	Seattle Mariners	.432	3	6	.333	.464	12	32	48	3-6	.308
27	Milwaukee Brewers	.419	2	6	.250	.475	29	23	44	2-6	.215
28	Texas Rangers	.399	4	6	.400	.398	27	37	51	3-7	.345
29	Houston Astros	.397	4	5	.444	.381	25	23	31	3-6	.355
30	Oakland Athletics	.393	5	5	.500	.358	13	56	33	7-3	.742

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.