For the most part, age is rarely discussed when talking about college quarterbacks. Outside of the Brandon Weedens and Chris Weinkes of the world, you generally don’t hear much from the draft community about the age of a prospect. But we do know that age matters, and that all other things being equal, being younger is better (or a sign that the player has a higher ceiling).

In this year’s draft, Tyler Bray is the neophyte, as he’ll be 21 years and 8 months old at the start of the season. He’s just weeks older than Matt Stafford and Josh Freeman were this time four years ago. It also means he’s 10 months younger than Geno Smith, the second youngest of the top prospects. On the other hand, Tyler Wilson will be 24 when the season starters, Landry Jones just turned 24, and Jordan “did you know Aaron is my brother” Rodgers will be 25 on August 30th. Do NFL teams generally ignore age — i.e., fail to measure younger quarterbacks against a lower bar? Or perhaps do they overemphasize age, thinking a young player has such high upside and can be taught anything that they ignore red flags? That’s what this post seeks to answer.

From 1970 to 2008, 587 quarterbacks were selected in the annual NFL draft. Unfortunately, I don’t have data on the age of the 195 players who never made it on to an NFL field. ^[1]The highest drafted quarterback never to appear in a game since 1970 was Arkansas State’s Gene Bradley, who was selected with the 37th pick by the Bills in 1980. However, I do have the dates of birth for the remaining 392 quarterbacks, which let’s us investigate how NFL teams value age.

First, we need to grade how well the quarterbacks performed. I decided to evaluate players through their first five seasons only, as I think that’s what teams consider when they select a player in the draft. I used a modified version of the formula from my Greatest Quarterback of All-Time Series: for each quarterback, I calculated his Adjusted Net Yards per Attempt average and the league ANY/A for each of his first five seasons. I then gave each passer credit for his ANY/A over replacement level — defined as 75% of league average — and multiplied that differential by his number of pass attempts (including sacks) to create a “value over replacement” statistic.

That’s a fancy way of saying I figured out which quarterback provided the most passing value over replacement in his first five years. Note that I did not include rushing in an attempt to keep it relatively simple. The results aren’t very surprising: Dan Marino has a huge lead on everyone else, with Peyton Manning and Matt Ryan at #2 and #3. Next, I converted the draft values from my Draft Value Chart into expected “adjusted net yardage over replacement” figures for these quarterbacks. After doing that, we can compare how much value above or below expectation each quarterback provided. Here are the results: the final column shows the player’s age on September 1st of the year he was drafted.

Rk	Name	Tm	Year	Pk	Exp Val	Act Val	Diff	Age
1	Dan Marino	MIA	1983	27	799	9091	8292	21.96
2	Boomer Esiason	CIN	1984	38	688	5605	4918	23.38
3	Peyton Manning	IND	1998	1	1861	6628	4766	22.44
4	Matt Ryan	ATL	2008	3	1507	6104	4597	23.29
5	Ken Anderson	CIN	1971	67	505	4530	4024	22.54
6	Joe Montana	SFO	1979	82	440	4459	4019	23.22
7	Tom Brady	NWE	2000	199	156	4129	3972	23.08
8	Brett Favre	ATL	1991	33	733	4286	3553	21.89
9	Jim Everett	HOU	1986	3	1507	4980	3473	23.66
10	Joe Flacco	BAL	2008	18	930	4372	3441	23.62
11	Aaron Brooks	GNB	1999	131	293	3433	3140	23.44
12	Daunte Culpepper	MIN	1999	11	1087	4194	3107	22.59
13	Carson Palmer	CIN	2003	1	1861	4771	2909	23.68
14	Ben Roethlisberger	PIT	2004	11	1087	3950	2863	22.5
15	Marc Bulger	NOR	2000	168	212	2844	2632	23.41
16	Jay Cutler	DEN	2006	11	1087	3715	2627	23.34
17	Mark Brunell	GNB	1993	118	323	2891	2568	22.96
18	Neil Lomax	STL	1981	33	733	3296	2563	22.54
19	Brian Griese	DEN	1998	91	409	2963	2554	23.46
20	Ken O'Brien	NYJ	1983	24	839	3371	2532	22.76
21	Mark Rypien	WAS	1986	146	257	2767	2509	23.92
22	Philip Rivers	NYG	2004	4	1416	3919	2502	22.73
23	Steve Grogan	NWE	1975	116	328	2803	2475	22.11
24	Drew Brees	SDG	2001	32	743	3171	2428	22.63
25	Aaron Rodgers	GNB	2005	24	839	3210	2371	21.75
26	Doug Williams	TAM	1978	17	951	3286	2336	23.06
27	Jeff Blake	NYJ	1992	166	212	2523	2311	21.74
28	Gus Frerotte	WAS	1994	197	161	2278	2117	23.09
29	Bert Jones	BAL	1973	2	1639	3559	1920	21.98
30	Drew Bledsoe	NWE	1993	1	1861	3781	1920	21.55
31	Jay Schroeder	WAS	1984	83	440	2352	1912	23.18
32	Chad Pennington	NYJ	2000	18	930	2836	1906	24.18
33	Pat Haden	RAM	1975	176	197	2097	1901	22.6
34	Neil O'Donnell	PIT	1990	70	490	2345	1855	24.16
35	Don Majkowski	GNB	1987	255	113	1789	1676	23.52
36	John Elway	BAL	1983	1	1861	3461	1599	23.18
37	Joe Ferguson	BUF	1973	57	561	2148	1587	23.36
38	Jason Campbell	WAS	2005	25	824	2202	1378	23.67
39	Matt Schaub	ATL	2004	90	409	1772	1363	23.19
40	Troy Aikman	DAL	1989	1	1861	3185	1324	22.78
41	Chris Miller	ATL	1987	13	1037	2347	1311	22.06
42	Tommy Kramer	MIN	1977	27	799	2104	1305	22.49
43	Elvis Grbac	SFO	1993	219	126	1323	1197	23.05
44	Tony Eason	NWE	1983	15	991	2187	1196	23.9
45	Craig Erickson	TAM	1992	86	424	1612	1187	23.29
46	Steve McNair	HOU	1995	3	1507	2570	1063	22.54
47	Charlie Batch	DET	1998	60	541	1602	1061	23.74
48	Kyle Orton	CHI	2005	106	359	1412	1053	22.8
49	Craig Erickson	PHI	1991	131	293	1338	1045	22.29
50	Matt Hasselbeck	GNB	1998	187	176	1203	1027	22.93
51	Byron Leftwich	JAX	2003	7	1234	2236	1002	23.63
52	Dan Fouts	SDG	1973	64	521	1518	997	22.23
53	Matt Cassel	NWE	2005	230	113	1019	905	23.29
54	Rodney Peete	DET	1989	141	268	1164	897	23.46
55	Jim McMahon	CHI	1982	5	1340	2178	838	23.03
56	Tony Banks	STL	1996	42	657	1493	836	23.41
57	Steve Pelluer	DAL	1984	113	338	1169	831	22.09
58	Donovan McNabb	PHI	1999	2	1639	2416	778	22.77
59	David Woodley	MIA	1980	214	131	903	772	21.85
60	Jim Kelly	BUF	1983	14	1011	1752	741	23.55
61	Jake Plummer	ARI	1997	42	657	1378	720	22.7
62	Ty Detmer	GNB	1992	230	113	804	691	24.84
63	Vince Ferragamo	RAM	1977	91	409	1099	689	23.36
64	Derek Anderson	BAL	2005	213	136	811	675	22.21
65	Steve DeBerg	DAL	1977	275	113	777	663	23.62
66	Steve Beuerlein	RAI	1987	110	348	1010	662	22.49
67	Brad Johnson	MIN	1992	227	113	774	661	23.97
68	Eli Manning	SDG	2004	1	1861	2506	645	23.66
69	Randall Cunningham	PHI	1985	37	698	1316	618	22.43
70	Stan Humphries	WAS	1988	159	227	797	570	23.38
71	Bill Kenney	MIA	1978	333	113	631	518	23.61
72	John Friesz	SDG	1990	138	273	747	474	23.29
73	Tim Rattay	SFO	2000	212	136	602	466	23.47
74	Chad Henne	MIA	2008	57	561	941	379	23.17
75	David Garrard	JAX	2002	108	354	732	378	24.54
76	Bubby Brister	PIT	1986	67	505	877	372	24.05
77	Brian Sipe	CLE	1972	330	113	469	356	23.07
78	Rich Gannon	NWE	1987	98	384	716	332	21.7
79	Mike Pagel	BAL	1982	84	435	742	308	21.97
80	Scott Mitchell	MIA	1990	93	399	698	299	22.66
81	Joe Gilliam	PIT	1972	273	113	401	287	21.68
82	Jim Harbaugh	CHI	1987	26	814	1097	283	23.69
83	Turk Schonert	CHI	1980	242	113	377	264	23.63
84	Troy Smith	BAL	2007	174	197	436	239	23.12
85	T.J. Rubley	RAM	1992	228	113	317	204	23.76
86	David Whitehurst	GNB	1977	206	146	333	187	22.35
87	Quincy Carter	DAL	2001	53	581	765	184	23.89
88	Matt Flynn	GNB	2008	209	141	307	166	23.2
89	Tyler Thigpen	MIN	2007	217	126	274	148	23.38
90	Eric Hipple	DET	1980	85	429	570	140	22.96
91	Jim Sorgi	IND	2004	193	166	298	132	23.75
92	Rob Johnson	JAX	1995	99	379	490	112	22.46
93	Doug Flutie	RAM	1985	285	113	225	112	22.86
94	Steve Dils	MIN	1979	97	389	485	96	23.73
95	Trent Edwards	BUF	2007	92	404	492	88	23.84
96	Paul McDonald	CLE	1980	109	348	422	74	22.52
97	Ed Luther	SDG	1980	101	374	416	42	23.66
98	Craig Nall	GNB	2002	164	217	238	21	23.36
99	Kent Graham	NYG	1992	211	136	157	21	23.83
100	Bob Avellini	CHI	1975	135	283	283	0	22.01
101	Patrick Ramsey	WAS	2002	32	743	740	-3	23.55
102	Tarvaris Jackson	MIN	2006	64	521	512	-9	23.36
103	Bucky Richardson	HOU	1992	220	126	110	-16	23.56
104	Tom Ramsey	NWE	1983	267	113	94	-19	22.15
105	Jack Trudeau	IND	1986	47	622	603	-19	23.98
106	Steve Matthews	KAN	1994	199	156	128	-28	23.89
107	Eric Zeier	CLE	1995	84	435	406	-29	22.98
108	Blair Kiel	TAM	1984	281	113	78	-35	22.76
109	Brooks Bollinger	NYJ	2003	200	156	107	-49	23.79
110	Gary Hogeboom	DAL	1980	133	288	234	-54	22.03
111	Shaun King	TAM	1999	50	601	539	-63	22.26
112	Mike Buck	NOR	1990	156	232	161	-71	23.36
113	Mike Moroski	ATL	1979	154	237	161	-76	21.99
114	Tom Owen	SFO	1974	322	113	29	-84	22
115	Michael Bishop	NWE	1999	227	113	20	-93	23.3
116	Glenn Foley	NYJ	1994	208	141	45	-96	23.89
117	Koy Detmer	PHI	1997	207	141	44	-97	24.16
118	Dan Orlovsky	DET	2005	145	257	158	-99	22.04
119	Dave Walter	NYG	1987	307	113	11	-102	22.73
120	Scott Brunner	NYG	1980	145	257	152	-106	23.44
121	Neal Jeffrey	SDG	1975	423	113	5	-108	22.11
122	Bob Gagliano	KAN	1981	319	113	3	-110	22.99
123	Sammy Garza	SEA	1987	216	131	21	-110	22.14
124	Kent Austin	STL	1986	312	113	0	-113	23.19
125	Joe Shield	GNB	1985	294	113	0	-113	23.18
126	Jeff Kelly	SEA	2002	232	113	0	-113	22.98
127	Rick Trocano	PIT	1981	292	113	0	-113	22.41
128	Bryan Clark	SFO	1982	251	113	0	-113	22.1
129	Matt Cavanaugh	NWE	1978	50	601	484	-117	21.85
130	Joe Hamilton	TAM	2000	234	113	-5	-118	23.47
131	Dennis Sproul	GNB	1978	200	156	38	-119	22.12
132	Gibran Hamdan	WAS	2003	232	113	-7	-120	22.56
133	Wally Richardson	BAL	1997	234	113	-7	-120	23.55
134	Alex Brink	HOU	2008	223	121	0	-121	23.25
135	Gifford Nielsen	HOU	1978	73	480	359	-121	23.85
136	Cliff Stoudt	PIT	1977	121	318	196	-122	22.43
137	Neil Graff	MIN	1972	414	113	-9	-122	22.64
138	Chris Greisen	ARI	1999	239	113	-9	-122	23.16
139	Scott Campbell	PIT	1984	191	171	49	-122	22.38
140	Billy Joe Tolliver	SDG	1989	51	596	474	-123	23.56
141	Rex Grossman	CHI	2003	22	865	742	-123	23.02
142	Trent Green	SDG	1993	222	121	-4	-125	23.15
143	Kyle Mackey	STL	1984	296	113	-12	-125	22.5
144	Vince Young	TEN	2006	3	1507	1379	-128	23.29
145	Gary Kubiak	DEN	1983	197	161	29	-132	22.05
146	Bob Holly	WAS	1982	291	113	-19	-132	22.25
147	Jay Walker	NWE	1994	198	156	23	-133	22.6
148	Scott Hunter	GNB	1971	140	268	131	-137	23.81
149	Mike Rae	OAK	1973	205	146	9	-137	22.1
150	Bradlee Van Pelt	DEN	2004	250	113	-25	-138	24.16
151	Kliff Kingsbury	NWE	2003	201	151	9	-142	24.06
152	Matt Mauck	DEN	2004	225	113	-29	-142	25.55
153	Pat Ryan	NYJ	1978	281	113	-31	-144	22.96
154	Jim Bob Taylor	BAL	1983	280	113	-32	-146	23.98
155	Scott Covington	CIN	1999	245	113	-34	-147	23.62
156	Larry Cipa	NOR	1974	373	113	-35	-148	22.91
157	Andre Woodson	NYG	2008	198	156	0	-156	24.35
158	Jeff Rutledge	RAM	1979	246	113	-44	-157	22.61
159	Todd Husak	WAS	2000	202	151	-10	-161	22.16
160	Reggie McNeal	CIN	2006	193	166	0	-166	22.95
161	Jarious Jackson	DEN	2000	214	131	-36	-166	23.33
162	Chris Chandler	IND	1988	76	465	296	-168	22.89
163	Chuck Clements	NYJ	1997	191	171	0	-171	23.92
164	Colt Brennan	WAS	2008	186	176	0	-176	25.05
165	J.T. O'Sullivan	NOR	2002	186	176	0	-176	23.02
166	Andy Hall	PHI	2004	185	182	0	-182	23.76
167	Dean Carlson	KAN	1972	179	192	8	-184	22.09
168	Randy Wright	GNB	1984	153	242	56	-186	23.64
169	Kerwin Bell	MIA	1988	180	187	0	-187	23.21
170	Craig Bradshaw	HOU	1980	182	187	0	-187	23.05
171	Bruce Mathison	SDG	1983	272	113	-76	-189	24.35
172	Mark Reed	NYG	1981	207	141	-48	-190	22.53
173	Doug Hudson	KAN	1987	186	176	-18	-194	22.97
174	Joe Barnes	CHI	1974	316	113	-81	-194	22.73
175	Sage Rosenfels	WAS	2001	109	348	153	-196	23.49
176	Mike Norseth	CLE	1986	174	197	0	-197	22.03
177	Seneca Wallace	SEA	2003	110	348	148	-200	23.07
178	David Humm	OAK	1975	128	298	93	-205	23.41
179	Jim Miller	PIT	1994	178	192	-19	-211	23.56
180	Babe Laufenberg	WAS	1983	168	212	0	-212	23.74
181	Steve Ramsey	NOR	1970	126	303	91	-212	22.36
182	Shawn Moore	DEN	1991	284	113	-99	-213	23.41
183	Dennis Dixon	PIT	2008	156	232	17	-215	23.64
184	Moses Moreno	CHI	1998	232	113	-103	-217	22.99
185	Terry Nugent	CLE	1984	158	232	15	-217	22.74
186	Bobby Scott	NOR	1971	340	113	-105	-219	22.41
187	Tony Adams	SDG	1973	343	113	-107	-220	23.48
188	Erik Ainge	NYJ	2008	162	222	0	-222	22.22
189	Mike Cherry	NYG	1997	171	207	-17	-224	23.71
190	Drew Henson	HOU	2003	192	166	-57	-224	23.55
191	Brian St. Pierre	PIT	2003	163	222	-4	-226	23.76
192	Steve Joachim	BAL	1975	160	227	0	-227	23.46
193	Tom Duniven	CIN	1977	160	227	0	-227	23.29
194	Reggie Collier	DAL	1983	162	222	-7	-229	22.3
195	Paul Justin	CHI	1991	190	171	-58	-230	23.29
196	Steve Bradley	CIN	1986	316	113	-121	-235	23.13
197	Brian McClure	BUF	1986	313	113	-122	-235	22.68
198	Gino Torretta	MIN	1993	192	166	-74	-241	23.06
199	Steve Bono	MIN	1985	142	262	22	-241	23.31
200	A.J. Feeley	PHI	2001	155	237	-4	-241	24.3
201	Dennis Morrison	SFO	1973	357	113	-128	-241	22.29
202	Frank Reich	BUF	1985	57	561	316	-245	23.74
203	Erik Wilhelm	CIN	1989	83	440	193	-246	23.78
204	Joe Reed	SFO	1971	283	113	-134	-247	23.65
205	Stan Gelbaugh	DAL	1986	150	247	0	-247	23.74
206	Jeff Rowe	CIN	2007	151	247	0	-247	23.45
207	Mike Kelley	ATL	1982	149	247	0	-247	22.67
208	Don Strock	MIA	1973	111	343	95	-249	22.76
209	Jeff Francis	RAI	1989	140	268	18	-249	23.15
210	Kevin Sweeney	DAL	1987	180	187	-65	-251	23.79
211	Ingle Martin	GNB	2006	148	252	0	-252	24.05
212	Kordell Stewart	PIT	1995	60	541	288	-252	22.87
213	Josh McCown	ARI	2002	81	445	192	-253	23.16
214	Frank Patrick	GNB	1970	251	113	-142	-255	23.48
215	Brent Pease	MIN	1987	295	113	-143	-257	22.9
216	Kerry Collins	CAR	1995	5	1340	1080	-260	22.67
217	Jeff George	IND	1990	1	1861	1601	-260	22.73
218	Carlos Brown	GNB	1975	296	113	-148	-261	23.09
219	John Witkowski	DET	1984	160	227	-37	-264	22.21
220	Vince Evans	CHI	1977	140	268	1	-267	22.22
221	Ken Dorsey	SFO	2003	241	113	-154	-268	22.36
222	Sam Adkins	SEA	1977	254	113	-156	-269	22.28
223	Tee Martin	PIT	2000	163	222	-47	-269	22.11
224	John David Booty	MIN	2008	137	278	0	-278	23.66
225	Norris Weese	RAM	1974	99	379	99	-280	23.06
226	Bill Musgrave	DAL	1991	106	359	78	-281	23.81
227	David Norrie	SEA	1986	291	113	-170	-283	22.75
228	Bruce Gradkowski	TAM	2006	194	166	-117	-283	23.59
229	Jordan Palmer	WAS	2007	205	146	-143	-289	23.26
230	Ben Bennett	ATL	1984	148	252	-43	-295	22.33
231	Rob Hertel	CIN	1978	131	293	-3	-296	23.53
232	Chris Simms	TAM	2003	97	389	85	-304	23.01
233	Cody Carlson	HOU	1987	64	521	216	-304	23.82
234	Tony Graziani	ATL	1997	204	146	-158	-304	23.69
235	John Navarre	ARI	2004	202	151	-163	-315	23.98
236	Chuck Fusina	TAM	1979	133	288	-27	-315	22.25
237	Craig Kupp	NYG	1990	135	283	-35	-318	23.38
238	Rohan Davey	NWE	2002	117	328	10	-318	24.38
239	Dean May	MIA	1984	138	273	-45	-318	22.27
240	Kevin Kolb	PHI	2007	36	708	386	-321	23.02
241	Alex Van Pelt	PIT	1993	216	131	-192	-323	23.34
242	Dave Barr	PHI	1995	119	323	-3	-326	23.31
243	Brad Smith	NYJ	2006	103	369	41	-328	22.72
244	Brock Huard	SEA	1999	77	460	123	-337	23.38
245	Scott Secules	DAL	1988	151	247	-90	-337	23.81
246	Matt Robinson	NYJ	1977	227	113	-224	-338	22.18
247	Luke McCown	CLE	2004	106	359	15	-344	23.14
248	Cody Pickett	SFO	2004	217	126	-218	-344	24.17
249	Pat Barnes	KAN	1997	110	348	0	-348	22.52
250	Dan Manucci	BUF	1979	116	328	-24	-352	21.99
251	Anthony Dilweg	GNB	1989	74	475	116	-359	24.43
252	Mark Manges	RAM	1978	105	364	0	-364	22.64
253	Cary Conklin	WAS	1990	86	424	60	-364	22.51
254	Perry Klein	ATL	1994	111	343	-21	-365	23.44
255	Doug Gaynor	CIN	1986	99	379	10	-369	23.16
256	Isaiah Stanback	DAL	2007	103	369	0	-369	23.04
257	Jeff Christensen	CIN	1983	137	278	-93	-371	23.65
258	Joe Theismann	MIA	1971	99	379	6	-373	21.98
259	Billy Joe Hobert	RAI	1993	58	551	178	-373	22.65
260	Mark Herrmann	DEN	1981	98	384	11	-373	22.65
261	Hugh Millen	RAM	1986	71	490	116	-374	22.78
262	Danny Kanell	NYG	1996	130	293	-104	-397	22.78
263	Troy Taylor	NYJ	1990	84	435	31	-404	22.41
264	Joe Germaine	STL	1999	101	374	-31	-405	24.06
265	Cliff Olander	SDG	1977	128	298	-107	-405	22.3
266	Kevin O'Connell	NWE	2008	94	399	-9	-408	23.27
267	Chris Redman	BAL	2000	75	470	53	-417	23.15
268	Michael Vick	ATL	2001	1	1861	1444	-418	21.18
269	Casey Weldon	PHI	1992	102	369	-54	-422	23.58
270	Jesse Freitas	SDG	1974	133	288	-141	-429	22.98
271	Doug Nussmeier	NOR	1994	116	328	-105	-434	23.72
272	Mark Vlasic	SDG	1987	88	419	-15	-434	23.85
273	Steve Stenstrom	KAN	1995	134	283	-157	-439	23.69
274	Jonathan Quinn	JAX	1998	86	424	-16	-440	23.51
275	Trent Dilfer	TAM	1994	6	1285	840	-445	22.47
276	Mike Wells	MIN	1973	80	450	0	-450	22.21
277	John Hufnagel	DEN	1973	348	113	-345	-458	21.97
278	Parnell Dickinson	TAM	1976	183	182	-281	-462	23.47
279	Josh Johnson	TAM	2008	160	227	-238	-465	22.3
280	Rick McIvor	STL	1984	80	450	-15	-465	23.93
281	Craig Penrose	DEN	1976	107	354	-134	-487	23.1
282	Glenn Carano	DAL	1977	54	576	88	-488	21.79
283	Mike Machurek	DET	1982	154	237	-254	-491	22.11
284	Jesse Palmer	NYG	2001	125	308	-184	-492	22.91
285	Charlie Whitehurst	SDG	2006	81	445	-48	-493	24.07
286	Danny White	DAL	1974	53	581	81	-500	22.56
287	Marc Wilson	OAK	1980	15	991	484	-507	23.54
288	Mark Malone	PIT	1980	28	789	275	-513	21.78
289	Donald Hollas	CIN	1991	99	379	-137	-516	23.78
290	Randy Dean	NYG	1977	117	328	-189	-517	22.23
291	Tom Flick	WAS	1981	90	409	-114	-523	23.01
292	J.P. Losman	BUF	2004	22	865	336	-529	23.47
293	Jeff Hostetler	NYG	1984	59	546	15	-531	23.36
294	Scott Zolak	NWE	1991	84	435	-97	-532	23.72
295	Wayne Clark	SDG	1970	198	156	-379	-535	23.26
296	Craig Krenzel	CHI	2004	148	252	-284	-536	23.17
297	Randy Fasani	CAR	2002	137	278	-274	-551	23.95
298	Ryan Fitzpatrick	STL	2005	250	113	-442	-555	22.77
299	Dave Ragone	HOU	2003	88	419	-136	-556	23.91
300	Tom Tupa	PHO	1988	68	500	-57	-557	22.57
301	Todd Collins	BUF	1995	45	637	78	-559	23.82
302	David Jaynes	KAN	1974	66	510	-51	-561	21.72
303	Kurt Kittner	ATL	2002	158	232	-333	-565	22.61
304	Jeff Lewis	DEN	1996	100	379	-200	-579	23.38
305	Chris Weinke	CAR	2001	106	359	-220	-579	29.09
306	Mike Kruczek	PIT	1976	47	622	35	-586	23.47
307	Kyle Boller	BAL	2003	19	910	320	-590	22.21
308	Steve Myer	SEA	1976	93	399	-203	-602	22.13
309	Mike Boryla	CIN	1974	87	424	-183	-607	23.49
310	Matt Leinart	ARI	2006	10	1118	508	-609	23.31
311	Brodie Croyle	KAN	2006	85	429	-183	-612	23.57
312	Bill Cappleman	MIN	1970	51	596	-17	-613	23.47
313	Wade Wilson	MIN	1981	210	141	-476	-617	22.58
314	Guy Benjamin	MIA	1978	51	596	-23	-619	23.18
315	Rusty Hilger	RAI	1985	143	262	-362	-624	23.32
316	Jerry Golsteyn	NYG	1976	333	113	-512	-626	22.07
317	Mike Kirkland	BAL	1976	143	262	-364	-627	22.18
318	Mike McMahon	DET	2001	149	247	-386	-633	22.56
319	Craig Whelihan	SDG	1995	197	161	-477	-638	24.38
320	Carl Summerell	NYG	1974	80	450	-194	-643	22.74
321	Marques Tuiasosopo	OAK	2001	59	546	-104	-650	22.45
322	Jeff Komlo	DET	1979	231	113	-547	-660	23.09
323	Peter Tom Willis	CHI	1990	63	526	-144	-670	23.66
324	Mark Miller	CLE	1978	68	500	-170	-670	22.05
325	Jeff Carlson	RAM	1989	102	369	-309	-678	23.28
326	Ron Jaworski	RAM	1973	37	698	14	-684	22.44
327	Oliver Luck	HOU	1982	44	642	-61	-703	22.41
328	Richard Todd	NYJ	1976	6	1285	568	-716	22.78
329	Leo Hart	ATL	1971	59	546	-178	-724	22.5
330	Todd Marinovich	RAI	1991	24	839	113	-726	22.16
331	Spergon Wynn	CLE	2000	183	182	-546	-728	22.06
332	Tony Sacca	PHO	1992	46	627	-101	-728	22.38
333	Matt Blundin	KAN	1992	40	672	-62	-734	23.49
334	Steve Fuller	KAN	1979	23	849	115	-735	22.65
335	Gary Keithley	STL	1973	45	637	-104	-741	22.64
336	Stoney Case	ARI	1995	80	450	-303	-753	23.15
337	Bobby Hoying	PHI	1996	85	429	-331	-760	23.95
338	Tom Hodson	NWE	1990	59	546	-221	-767	23.59
339	Drew Stanton	DET	2007	43	647	-124	-771	23.32
340	Randy Hedberg	TAM	1977	196	161	-616	-778	22.68
341	Mike Elkins	KAN	1989	32	743	-48	-791	23.12
342	Will Furrer	CHI	1992	107	354	-440	-794	24.57
343	Brian Brohm	GNB	2008	56	566	-229	-795	22.94
344	John Beck	MIA	2007	40	672	-130	-802	26.03
345	Kellen Clemens	NYJ	2006	49	607	-218	-825	23.24
346	Scott Bull	SFO	1976	177	192	-637	-829	23.23
347	Jeb Blount	OAK	1976	50	601	-242	-843	22.14
348	Joey Harrington	DET	2002	3	1507	662	-845	23.86
349	Brady Quinn	CLE	2007	22	865	1	-864	22.84
350	Charlie Frye	CLE	2005	67	505	-365	-871	24.01
351	Jim Plunkett	NWE	1971	1	1861	987	-875	23.74
352	Browning Nagle	NYJ	1991	34	723	-176	-899	23.34
353	Lynn Dickey	HOU	1971	56	566	-345	-912	21.87
354	Cade McNown	CHI	1999	12	1062	131	-931	22.63
355	Gary Marangi	BUF	1974	70	490	-450	-940	22.09
356	Matt Kofler	BUF	1982	48	612	-329	-940	23.01
357	Tim Couch	CLE	1999	1	1861	899	-962	22.09
358	Chuck Long	DET	1986	12	1062	84	-978	23.53
359	Jim Druckenmiller	SFO	1997	26	814	-170	-984	24.95
360	Danny Wuerffel	NOR	1997	99	379	-608	-987	23.27
361	Rusty Lisch	STL	1980	89	414	-583	-997	23.7
362	Steve Pisarkiewicz	STL	1977	19	910	-104	-1014	23.81
363	Dennis Shaw	BUF	1970	30	763	-286	-1050	23.5
364	Pat Sullivan	ATL	1972	40	672	-379	-1051	22.62
365	David Carr	HOU	2002	1	1861	792	-1069	23.12
366	Phil Simms	NYG	1979	7	1234	146	-1088	24.83
367	Andrew Walter	OAK	2005	69	495	-599	-1094	23.31
368	Tommy Maddox	DEN	1992	25	824	-291	-1115	21
369	Todd Blackledge	KAN	1983	7	1234	56	-1178	22.51
370	Jerry Tagge	GNB	1972	11	1087	-119	-1206	22.39
371	Andre Ware	DET	1990	7	1234	-2	-1236	22.09
372	John Reaves	PHI	1972	14	1011	-251	-1262	22.5
373	Dan McGwire	SEA	1991	16	966	-312	-1278	23.7
374	Kelly Stouffer	STL	1987	6	1285	-180	-1464	23.15
375	Dan Pastorini	HOU	1971	3	1507	-17	-1524	22.27
376	Jack Thompson	CIN	1979	3	1507	-42	-1549	23.29
377	Gary Huff	CHI	1973	33	733	-821	-1554	22.35
378	Vinny Testaverde	TAM	1987	1	1861	306	-1555	23.8
379	David Klingler	CIN	1992	6	1285	-292	-1577	23.54
380	Rich Campbell	GNB	1981	6	1285	-297	-1582	22.69
381	Kim McQuilken	ATL	1974	69	495	-1276	-1772	23.51
382	Steve Bartkowski	ATL	1975	1	1861	45	-1816	22.8
383	Heath Shuler	WAS	1994	3	1507	-330	-1837	22.67
384	Alex Smith	SFO	2005	1	1861	-48	-1909	21.32
385	Art Schlichter	BAL	1982	4	1416	-493	-1909	22.35
386	Rick Mirer	SEA	1993	2	1639	-278	-1917	23.46
387	Mike Phipps	CLE	1970	3	1507	-484	-1991	22.78
388	Archie Manning	NOR	1971	2	1639	-379	-2017	22.29
389	JaMarcus Russell	OAK	2007	1	1861	-236	-2097	22.06
390	Akili Smith	CIN	1999	3	1507	-631	-2138	24.03
391	Terry Bradshaw	PIT	1970	1	1861	-311	-2172	22
392	Ryan Leaf	SDG	1998	2	1639	-882	-2521	22.3

Next, I plotted each quarterback on a graph, with age on the X-axis and the Differential column (value over replacement over expectation) on the Y-axis. Note that Dan Marino’s data point is off the chart, but he was included in the underlying file.

It’s pretty easy to see that there’s no relationship between age and draft selection. If teams undervalued age, then more of the dots would be up and to the left; if teams overvalued age, then there would be a disproportionate number of dots down and to the right. I’ve included a best-fit trendline in a thick black line, and as you can see, it essentially rides along the expectation line, confirming that NFL teams have not been under- or over-valuing age.

This doesn’t mean that age is irrelevant, but rather that NFL teams are properly balancing age with every other variable. If you believe the draft is an efficient market, this would reinforce that belief. Players like Michael Vick, Alex Smith, and Drew Bledsoe were first overall picks in part because of their age. So if Tyler Bray gets drafted earlier than you might expect, that’s a sign that an NFL team considers his track record in connection with his youth. On the other hand, if he falls in the draft, it’s unlikely that it’s because NFL teams ignore his age: it just means that his youth can’t compensate for his other issues. Mock drafters and draftniks may undervalue age (at least, in my opinion) but it doesn’t appear that NFL teams are guilty of the same mistake.