Where does Verlander Rank Among Tigers ERA+ Leaders?

In the previous post, the ERA+ statistic was defined and its interpretation clarified.  In this post, it will be used to rank the top Tigers pitchers of all time.  I believe I did something similar on this blog a few years ago, but that was before current ace Justin Verlander had enough innings to qualify and before he had his elite 2011 season. The table below lists the top 15 Detroit hurlers of all time, only including their years with the Tigers.

The first six columns of the table should be self explanatory.  If you read the previous ERA+ post linked above, you might remember that the interpretation of ERA+ is a bit tricky.  So, I've added another column to the table (%) which tells us how far below the league average the pitcher's ERA fell.  For example, Hall-of-Famer southpaw Hal Newhouser had a career ERA+ of 130 which which means his ERA was 23% better than the average pitcher over the course of his career.  In order to qualify, a pitcher needs 150 career starts.

Table 1: All-time Tigers ERA+ Leaders

Player	From	To	IP	ERA	ERA+	%
Hal Newhouser	1939	1953	2,944	3.07	130	23
Tommy Bridges	1930	1946	2,826	3.57	126	21
Dizzy Trout	1939	1952	2,591	3.20	125	20
Justin Verlander	2005	2011	1,315	3.54	124	19
Frank Lary	1954	1964	2,008	3.46	116	14
Jim Bunning	1955	1963	1,867	3.45	116	14
Schoolboy Rowe	1933	1942	1,445	4.01	114	12
Virgil Trucks	1941	1956	1,800	3.50	114	12
Fred Hutchinson	1939	1953	1,464	3.73	113	12
Denny McLain	1963	1970	1,593	3.13	110	9
Ed Killian	1904	1910	1,536	2.38	110	9
Bill Donovan	1903	1918	2,137	2.49	109	8
Jack Morris	1977	1990	3,042	3.73	108	7
Dan Petry	1979	1991	1,843	3.84	105	5
Mickey Lolich	1963	1975	3,361	3.45	105	5

Data source: Baseball-Reference.com

In his seven seasons with the Tigers. Verlander has an ERA+ of 124 which makes him 19% better than average.  He ranks fourth all time behind Newhouser, Tommy Bridges and Dizzy Trout.  Verlander's total includes his 2008 season where he had an ERA+ of 93.  In each of his other
seasons, he had ERA+ of at least 124.  We can't very well throw out his worst season, but he certainly has an excellent chance to raise his ERA+ in the future. 

One thing you might notice on the chart is that Jack Morris falls slightly below Denny McLain and Ed Killian in ERA+, but pitched almost twice as many innings.  So, Morris was very close to McLain and Killian in quality, but does not get credit for his much larger workload.  That is because ERA+ measures quality only and not quantity.  There are other measures which combine quality and quantity which will be covered later.