## Era-Adjusted TD/INT Ratios

On Saturday, I asked the question: Is TD/INT Ratio Now Meaningless? That question was shorthand for a less hot-takey view, but fortunately I’m lucky enough to have smart readers who engaged in some excellent discussion in the comments. One of those guys, Bryan Frye, brought up the idea of a TD/INT+ Ratio, or an era-adjusted version.

I spent a bit of time playing with different ways to adjust for era, including using Z-Scores. One problem there was that the variance in TD and INT Rates is pretty significant from year to year, which makes the Z-Score heavily influenced more by year-to-year fluctuation that true era adjustments. So here’s what I did, using Milt Plum in 1960 and Tom Brady in 2010 as examples. Those two players rank 4th and 5th in this system despite playing 50 years apart. The raw numbers? Brady had a 9:1 TD/INT Ratio with 36 TDs and 4 INTs, while Plus was at 4.2:1, courtesy of 21 TDs and 5 INTs.

1) First, we convert to rates. Plum threw 250 passes, while Brady had almost exactly double, with 492 attempts. Plum averaged 8.40 TD/100Att, while Brady was at 7.32 TD/100Att. On the other hand, Plum was at 2.00 INT/100Att, vs. 0.81 INT/100Att for Brady.

2) Next, we adjust for era, using only players who had enough pass attempts to qualify for the league passing crown, and taking a simple average of the rates of those players. Therefore, for the 1960 NFL season, the TD/100Att average was 5.34, while the INT/100Att average was 7.13. So Plum was at 157% of league average at throwing touchdowns and 357% of league average at avoiding interceptions.

Brady? Well, in 2010, the qualifying passers averaged 4.47 touchdowns and 2.78 interceptions per 100 pass attempts. This means he was at 164% of league average in touchdowns and 342% at avoiding interceptions

3) Finally, we multiply the two rates. So Plum’s Adjusted TD Rate times his Adjusted INT Rate was 5.61, while Brady was at 5.60.

Here are the top 300 seasons by this measure. The best season came from yes, Damon Huard in 2006. Here’s how to read the table below. Playing with the Chiefs, Huard threw 11 TDs and just 1 INT in 2006, an 11.00 TD/INT Ratio (the 3rd best ever). He threw 244 attempts that year, and averaged 4.51 TDs per 100 pass attempts. The league average was 3.89, so Huard was at 116% of league average. He threw just 0.41 interceptions per 100 attempts, while the league average was 3.05. That gives him an INT+ of 745%. Multiply those two numbers — 116% and 745% — and you get a value of 8.63, which ranks as the best era-adjusted TD/INT rate of all time.

RkQBTeamYearTDINTTD/INTAttTD/ALgAvgTD+INT/ALgAvgINT+VALUE
1Damon HuardKAN200611111.002444.513.89116%0.413.05745%8.63
2Nick FolesPHI201327213.503178.524.51189%0.632.67423%7.98
3Josh McCownCHI201313113.002245.804.51129%0.452.67597%7.68
4Milt PlumCLE19602154.202508.405.34157%2.007.13357%5.61
6Aaron RodgersGNB20114567.505028.964.31208%1.202.89242%5.03
7Bart StarrGNB19661434.672515.584.69119%1.204.76399%4.74
9David GarrardJAX20071836.003255.544.18133%0.923.09335%4.45
10Steve DeBergKAN19902345.754445.184.37118%0.903.34370%4.39
11Roger StaubachDAL19711543.752117.114.52157%1.905.28279%4.38
12Aaron RodgersGNB20143857.605207.314.55161%0.962.50260%4.18
13Steve BartkowskiATL19832254.404325.094.56112%1.164.32374%4.17
14Brian GrieseDEN20001944.753365.654.09138%1.193.21269%3.72
15Bart StarrGNB19641543.752725.515.09108%1.474.72321%3.48
16Brett FavreMIN20093374.715316.214.23147%1.323.08234%3.43
17Steve YoungSFO19922573.574026.224.03154%1.743.75215%3.32
18Peyton ManningIND200449104.904979.864.53218%2.013.02150%3.27
19Peyton ManningDEN201355105.506598.354.51185%1.522.67176%3.25
20Charlie ConerlyNYG19591443.501947.225.60129%2.065.17251%3.23
21Vinny TestaverdeNYJ19982974.144216.894.23163%1.663.27197%3.20
22Dan MarinoMIA19832063.332966.764.56148%2.034.32213%3.16
23Aaron RodgersGNB20093074.295415.554.23131%1.293.08238%3.12
24Ken O'BrienNYJ19852583.134885.124.20122%1.644.17254%3.10
25Joe MontanaSFO19892683.253866.744.10164%2.073.79183%3.00
26Aaron RodgersGNB20123984.885527.074.28165%1.452.62180%2.98
27Bert JonesBAL19762492.673437.004.24165%2.624.73180%2.98
28Johnny UnitasBAL19581972.712637.225.17140%2.665.66213%2.97
29Johnny UnitasBAL19641963.173056.235.09122%1.974.72240%2.94
30Steve YoungSFO199435103.504617.593.82199%2.173.17146%2.91
31Neil O'DonnellCIN19981543.753434.374.23103%1.173.27280%2.90
32Phil SimmsNYG19901543.753114.824.37110%1.293.34259%2.86
33Sid LuckmanCHI194328122.3320213.868.66160%5.9410.56178%2.85
34Roman GabrielRAM19692473.433996.025.44111%1.754.50256%2.83
35Steve McNairTEN20032473.434006.004.00150%1.753.30189%2.83
36Babe ParilliBOS19621882.252537.115.52129%3.166.82216%2.78
37John BrodieSFO197024102.403786.354.34146%2.655.02190%2.78
38Ken AndersonCIN198129102.904796.054.26142%2.094.05194%2.76
39Peyton ManningIND20063193.445575.573.89143%1.623.05189%2.70
40Jim HartSTL19742082.503885.154.15124%2.064.48217%2.70
41Sammy BaughWAS19451142.751826.045.74105%2.205.56253%2.66
42Sonny JurgensenWAS197023102.303376.824.34157%2.975.02169%2.66
43Roger StaubachDAL197927112.454615.864.23139%2.394.56191%2.65
44Randall CunninghamMIN199834103.404258.004.23189%2.353.27139%2.63
47Otto GrahamCLE19551581.881858.114.98163%4.326.88159%2.59
48Josh FreemanTAM20102564.174745.274.47118%1.272.78219%2.59
49Bert JonesBAL19751882.253445.234.38120%2.335.02216%2.58
50Donovan McNabbPHI20043183.884696.614.53146%1.713.02177%2.58
53Drew BreesSDG20042773.864006.754.53149%1.753.02173%2.57
54Kurt WarnerSTL199941133.154998.224.05203%2.613.30127%2.57
55Brett FavreGNB199639133.005437.183.99180%2.393.41142%2.57
56Tony EasonNWE19842382.884315.344.51118%1.863.94212%2.51
57Trent GreenSTL20001653.202406.674.09163%2.083.21154%2.51
58Joe TheismannWAS198329112.644596.324.56139%2.404.32180%2.50
59Rich GannonOAK20012793.005494.923.94125%1.643.25198%2.48
60Craig MortonDAL19701572.142077.254.34167%3.385.02148%2.48
61Aaron BrooksNOR20032483.005184.634.00116%1.543.30214%2.48
62Bubby BristerPHI19931452.803094.533.57127%1.623.15195%2.48
63Dan MarinoMIA198448172.825648.514.51189%3.013.94131%2.47
64Bob GrieseMIA19711992.112637.224.52160%3.425.28154%2.47
65Len DawsonKAN196626102.602849.155.41169%3.525.09145%2.45
66Joe MontanaSFO198428102.804326.484.51144%2.313.94170%2.45
67Robert GriffinWAS20122054.003935.094.28119%1.272.62206%2.45
68Steve BonoSFO19911142.752374.643.62128%1.693.21190%2.44
69Jeff GarciaSFO200031103.105615.534.09135%1.783.21180%2.43
70Jeff GarciaTAM20071343.253273.984.1895%1.223.09253%2.41
71Matt CasselKAN20102773.864506.004.47134%1.562.78179%2.40
72Roger StaubachDAL19771892.003614.994.20119%2.495.04202%2.40
73Peyton ManningIND200329102.905665.124.00128%1.773.30187%2.39
74Fran TarkentonNYG19692382.884095.625.44103%1.964.50230%2.38
75Fran TarkentonMIN19761782.134124.134.2497%1.944.73244%2.37
75Greg LandryDET19761782.132915.844.24138%2.754.73172%2.37
77Tommy ThompsonPHI194825112.2724610.166.66153%4.476.93155%2.37
78Daunte CulpepperMIN200439113.555487.124.53157%2.013.02150%2.36
79Seneca WallaceSEA20081133.672424.553.95115%1.242.54205%2.36
80Marc BulgerSTL20062483.005884.083.89105%1.363.05224%2.35
81Donovan McNabbPHI20061863.003165.703.89146%1.903.05161%2.35
82Boomer EsiasonCIN198928112.554556.154.10150%2.423.79157%2.35
83Ken StablerOAK197426122.173108.394.15202%3.874.48116%2.34
84Chris MillerATL19921562.502535.934.03147%2.373.75158%2.32
85Jim HarbaughIND19951753.403145.414.12132%1.592.81177%2.32
86Steve YoungSFO199836123.005176.964.23165%2.323.27141%2.32
87Frankie AlbertSFO194829102.9026410.986.38172%3.795.07134%2.31
89Frank FilchockWAS19441391.441478.846.46137%6.1210.23167%2.29
90Alex SmithSFO20111753.404453.824.3189%1.122.89258%2.28
91Tommy KramerMIN198624102.403726.453.94164%2.693.74139%2.28
93Ron JaworskiPHI198027122.254515.994.49133%2.664.52170%2.26
94Mark RypienWAS199128112.554216.653.62184%2.613.21123%2.26
95Sonny JurgensenWAS196731161.945086.104.88125%3.155.70181%2.26
96Drew BreesNOR200934113.095146.614.23156%2.143.08144%2.25
97Roman GabrielRAM196725131.923716.744.88138%3.505.70163%2.24
98Boomer EsiasonCIN198527122.254316.264.20149%2.784.17150%2.23
99Jeff GeorgeOAK19972993.225215.573.98140%1.732.74158%2.22
100John ElwayDEN199325102.505514.543.57127%1.813.15174%2.21
100Troy AikmanDAL19931562.503923.833.57107%1.533.15206%2.21
102Fran TarkentonMIN197525131.924255.884.38134%3.065.02164%2.21
103Drew BreesNOR201146143.296577.004.31162%2.132.89136%2.21
104Jeff GarciaSFO200132122.675046.353.94161%2.383.25137%2.20
106Ken AndersonCIN197521111.913775.574.38127%2.925.02172%2.19
107Cecil IsbellGNB194115111.362067.285.27138%5.348.46158%2.19
109Steve YoungSFO19971963.173565.343.98134%1.692.74162%2.18
110Michael VickPHI20102163.503725.654.47126%1.612.78172%2.18
111Ben RoethlisbergerPIT200732112.914047.924.18190%2.723.09114%2.16
112Brian SipeCLE198030142.145545.424.49121%2.534.52179%2.16
113Russell WilsonSEA20153484.254837.044.59153%1.662.32140%2.15
115Byron LeftwichJAX20051553.003024.974.07122%1.662.88174%2.12
116Ben RoethlisbergerPIT20101753.403894.374.4798%1.292.78216%2.12
117Cecil IsbellGNB194224141.712688.965.51163%5.226.79130%2.11
118Johnny UnitasBAL195932142.293678.725.60156%3.815.17136%2.11
119Len DawsonDTX196229171.713109.355.52170%5.486.82124%2.11
120Sammy BaughWAS194725151.673547.066.56108%4.248.29196%2.11
121Frank RyanCLE196629142.073827.594.69162%3.664.76130%2.11
122Y.A. TittleNYG196336142.573679.815.82169%3.814.76125%2.10
123Tony RomoDAL20092692.895504.734.23112%1.643.08188%2.10
124Craig MortonDEN19771481.752545.514.20131%3.155.04160%2.10
125Doug FlutieBUF2000832.672313.464.0985%1.303.21247%2.09
126Len DawsonKAN19681791.892247.595.08149%4.025.61140%2.09
127Jim HardyRAM19481472.002116.646.66100%3.326.93209%2.08
128Tony RomoDAL201131103.105225.944.31138%1.922.89151%2.08
129Tony RomoDAL20143493.784357.824.55172%2.072.50121%2.08
131Neil LomaxSTL198324112.183546.784.56149%3.114.32139%2.07
132Joe MontanaSFO198527132.084945.474.20130%2.634.17158%2.06
133Peyton ManningDEN201237113.365836.354.28148%1.892.62139%2.06
134Joe MontanaSFO198326122.175155.054.56111%2.334.32186%2.05
135Jim KellyBUF19902492.673466.944.37159%2.603.34128%2.03
136Don MeredithDAL196624122.003446.984.69149%3.494.76137%2.03
137Bob GrieseMIA197722131.693077.174.20170%4.235.04119%2.03
138Norm Van BrocklinRAM195018141.292337.734.88158%6.017.69128%2.03
139Carson PalmerARI20141133.672244.914.55108%1.342.50187%2.02
141Dave KriegSEA19881882.252287.894.05195%3.513.63103%2.02
142Donovan McNabbPHI20071972.714734.024.1896%1.483.09209%2.01
143Len DawsonKAN196430181.673548.475.42156%5.086.53128%2.01
144George BlandaHOU196136221.643629.945.12194%6.086.27103%2.00
145Roger StaubachDAL197825161.564136.054.03150%3.875.17133%2.00
146Brett FavreGNB199538132.925706.674.12162%2.282.81123%2.00
147Rich GannonOAK200028112.554735.924.09145%2.333.21138%2.00
148Steve YoungSFO19961462.333164.433.99111%1.903.41180%2.00
150Don MeredithDAL19621581.882127.085.61126%3.775.96158%1.99
151Donovan McNabbPHI20021762.833614.714.09115%1.662.87173%1.99
152Ben RoethlisbergerPIT20122683.254495.794.28135%1.782.62147%1.99
153Roman GabrielRAM197117101.703524.834.52107%2.845.28186%1.99
154Sammy BaughWAS194012101.201776.784.14164%5.656.84121%1.99
155Peyton ManningIND200528102.804536.184.07152%2.212.88131%1.98
156Erik KramerCHI199529102.905225.564.12135%1.922.81147%1.98
157James HarrisRAM19741161.831985.564.15134%3.034.48148%1.98
158Bobby ThomasonPHI19551071.431715.854.98117%4.096.88168%1.98
159Marty DomresBAL19721161.832224.954.64107%2.704.98184%1.97
160Chris ChandlerATL19972072.863425.853.98147%2.052.74134%1.97
161Brett FavreGNB199433142.365825.673.82149%2.413.17132%1.96
162Aaron RodgersGNB20153183.885725.424.59118%1.402.32166%1.96
163Ben RoethlisbergerPIT20143293.566085.264.55116%1.482.50169%1.96
164Otto GrahamCLE194725112.272699.297.37126%4.096.34155%1.96
165Steve BeuerleinCAR199936152.405716.304.05156%2.633.30126%1.95
166Bernie KosarCLE19872292.443895.664.62123%2.313.69159%1.95
167Steve BartkowskiATL198031161.944636.704.49149%3.464.52131%1.95
168Ken AndersonCIN197418101.803285.494.15132%3.054.48147%1.94
169Alex SmithKAN20132373.295084.534.51100%1.382.67193%1.94
170Warren MoonHOU199033132.545845.654.37129%2.233.34150%1.94
171Matt RyanATL20102893.115714.904.47110%1.582.78176%1.94
172Paul GovernaliBOS194613101.301926.776.09111%5.219.03173%1.93
173Drew BreesNOR201339123.256506.004.51133%1.852.67144%1.92
174Ken O'BrienNYJ19881572.144243.544.0587%1.653.63220%1.92
176Joe MontanaSFO198731132.383987.794.62169%3.273.69113%1.91
177Warren MoonHOU19881782.132945.784.05143%2.723.63133%1.91
178Butch SonginBOS19611491.562126.605.12129%4.256.27148%1.90
179Ray LucasNYJ19991462.332725.154.05127%2.213.30150%1.90
180Fran TarkentonMIN19731572.142745.475.06108%2.554.48176%1.90
181Matt HasselbeckSEA20052492.674495.354.07131%2.002.88144%1.89
182Carson PalmerCIN200532122.675096.294.07154%2.362.88122%1.89
183Norm Van BrocklinPHI196024171.412848.455.34158%5.997.13119%1.89
184Steve YoungSFO19911782.132796.093.62168%2.873.21112%1.89
185Bob GrieseMIA19731782.132187.805.06154%3.674.48122%1.88
186Richard ToddNYJ19821481.752615.364.08132%3.074.38143%1.88
187Daunte CulpepperMIN200325112.274545.514.00138%2.423.30136%1.88
188Bill KenneyKAN19851791.893385.034.20120%2.664.17156%1.87
189Fran TarkentonMIN196422112.003067.195.09141%3.594.72131%1.86
190Troy AikmanDAL19981252.403153.814.2390%1.593.27206%1.86
191Billy KilmerWAS197219111.732258.444.64182%4.894.98102%1.85
192Drew BreesNOR200626112.365544.693.89121%1.993.05154%1.85
193Bert JonesBAL197717111.553934.334.20103%2.805.04180%1.85
194Charlie ConerlyNYG195417111.552108.105.19156%5.246.21118%1.85
195Dan FoutsSDG198133171.946095.424.26127%2.794.05145%1.85
196Daryle LamonicaOAK196825151.674166.015.08118%3.615.61155%1.84
197Mark MalonePIT19851371.862335.584.20133%3.004.17139%1.84
198Tony RomoDAL201331103.105355.794.51128%1.872.67143%1.83
199Fran TarkentonNYG197019121.583894.884.34113%3.085.02163%1.83
200Richard ToddNYJ198125131.924975.034.26118%2.624.05155%1.83
201Rich GannonOAK200226102.606184.214.09103%1.622.87178%1.82
202Scott MitchellDET199532122.675835.494.12133%2.062.81137%1.82
203Jake PlummerDEN20051872.574563.954.0797%1.542.88188%1.82
204Dan MarinoMIA198644231.916237.063.94179%3.693.74101%1.82
205Dave KriegSEA198621111.913755.603.94142%2.933.74128%1.81
206Andy DaltonCIN20152573.573866.484.59141%1.812.32128%1.81
207Tony EasonNWE198619101.904484.243.94108%2.233.74168%1.81
208Billy KilmerWAS19741061.672344.274.15103%2.564.48175%1.80
209Milt PlumCLE196118101.803025.965.49109%3.315.47165%1.79
210Brian SipeCLE197821151.403995.264.03131%3.765.17137%1.79
212Boomer EsiasonCIN198828142.003887.224.05178%3.613.63101%1.79
213Sammy BaughWAS194216111.452257.115.51129%4.896.79139%1.79
214Norm Van BrocklinRAM195319141.362866.644.90136%4.906.45132%1.79
215Fran TarkentonNYG196729191.533777.694.88157%5.045.70113%1.78
216Rich GannonMIN19911262.003543.393.6294%1.693.21190%1.78
216Bernie KosarCLE19911892.004943.643.62101%1.823.21176%1.78
218Ken StablerOAK197627171.592919.284.24219%5.844.7381%1.77
220Cam NewtonCAR201535103.504967.064.59154%2.022.32115%1.77
221Mark BrunellJAX19971872.574354.143.98104%1.612.74170%1.77
222Jake PlummerDEN20031572.143024.974.00124%2.323.30142%1.77
223Neil O'DonnellPIT19931472.004862.883.5781%1.443.15219%1.77
224Babe ParilliBOS19611391.441986.575.12128%4.556.27138%1.77
225Brett FavreGNB200132152.135106.273.94159%2.943.25111%1.76
226Charlie ConerlyNYG194822131.692997.366.66110%4.356.93160%1.76
227Craig MortonDEN19781181.382674.124.03102%3.005.17172%1.76
228Randall CunninghamPHI199030132.314656.454.37148%2.803.34119%1.76
229Y.A. TittleNYG196233201.653758.805.61157%5.335.96112%1.75
231Tony BanksBAL19991782.133205.314.05131%2.503.30132%1.73
232Matt HasselbeckSEA200728122.335624.984.18119%2.143.09145%1.73
233Ken AndersonCIN197916101.603394.724.23112%2.954.56155%1.73
234Charlie ConerlyNYG19561071.431745.754.95116%4.025.97148%1.72
235Peyton ManningIND200033152.205715.784.09141%2.633.21122%1.72
236Jim KellyBUF199133171.944746.963.62192%3.593.2190%1.72
237Donovan McNabbPHI200125122.084935.073.94129%2.433.25134%1.72
238Jim HarbaughIND19971042.503093.243.9881%1.292.74211%1.72
239Matthew StaffordDET201141162.566636.184.31143%2.412.89120%1.72
241Mark BrunellJAX19982092.223545.654.23134%2.543.27129%1.72
242Sonny JurgensenWAS196424131.853856.235.09123%3.384.72140%1.71
243Rudy BukichCHI19652092.223126.415.85110%2.884.51156%1.71
244Phil SimmsNYG198821111.914794.384.05108%2.303.63158%1.71
245Russell WilsonSEA20132692.894076.394.51142%2.212.67121%1.71
246Tommy ThompsonPHI194916111.452147.485.50136%5.146.46126%1.71
247Dan MarinoMIA199125131.925494.553.62126%2.373.21136%1.71
248Mark BrunellJAX20021772.434164.094.09100%1.682.87171%1.70
249John ElwayDEN199822102.203566.184.23146%2.813.27116%1.70
250Len DawsonKAN196521141.503056.894.65148%4.595.27115%1.70
251Roman GabrielPHI197323121.924605.005.0699%2.614.48172%1.70
252Daryle LamonicaOAK197022151.473566.184.34142%4.215.02119%1.70
254Johnny UnitasBAL195724171.413017.975.08157%5.656.10108%1.70
255Carson PalmerCIN200628132.155205.383.89138%2.503.05122%1.69
256John ElwayDEN199727112.455025.383.98135%2.192.74125%1.69
257Joe FergusonBUF197525171.473217.794.38178%5.305.0295%1.69
259Tyrod TaylorBUF20152063.333805.264.59115%1.582.32147%1.69
260Matt SchaubHOU20111562.502925.144.31119%2.052.89141%1.68
261Joe MontanaSFO19801591.672735.494.49122%3.304.52137%1.68
262Aaron RodgersGNB20131762.832905.864.51130%2.072.67129%1.67
263Neil O'DonnellNYJ19971772.434603.703.9893%1.522.74180%1.67
264Virgil CarterCIN19711071.432224.504.52100%3.155.28168%1.67
265Joe TheismannWAS197920131.543955.064.23120%3.294.56139%1.66
266Neil O'DonnellPIT19951772.434164.094.1299%1.682.81167%1.66
269Joe MontanaSFO198217111.553464.914.08121%3.184.38138%1.66
267Dan FoutsSDG198217111.553305.154.08126%3.334.38131%1.66
270Bill NelsenCLE196819101.902936.485.54117%3.414.83141%1.66
271Charlie ConerlyNYG195213101.301697.695.51140%5.927.01118%1.65
272Alex SmithKAN20141863.004643.884.5585%1.292.50194%1.65
273Trent GreenKAN200324122.005234.594.00115%2.293.30144%1.65
274Billy KilmerWAS197523161.443466.654.38152%4.625.02109%1.65
275Y.A. TittleSFO195320161.252597.724.90158%6.186.45104%1.65
276Joe MontanaKAN19931371.862984.363.57122%2.353.15134%1.64
277Peyton ManningIND200731142.215156.024.18144%2.723.09114%1.64
278Bill MunsonDET19681581.883294.565.5482%2.434.83198%1.63
279Neil LomaxPHO198820111.824434.514.05111%2.483.63146%1.63
280Mark BrunellWAS200523102.304545.074.07124%2.202.88131%1.63
281Steve WalshNOR19911161.832554.313.62119%2.353.21137%1.63
282Matt RyanATL201129122.425665.124.31119%2.122.89137%1.62
283Jeff KempRAM19841371.862844.584.51102%2.463.94160%1.62
284Ron JaworskiPHI197918121.503744.814.23114%3.214.56142%1.62
285Daryle LamonicaOAK196730201.504257.065.26134%4.715.67121%1.62
286Trent GreenWAS199823112.095094.524.23107%2.163.27151%1.62
287Daunte CulpepperMIN200033162.064746.964.09170%3.383.2195%1.62
289Bernie KosarCLE198617101.705313.203.9481%1.883.74199%1.62
290Milt PlumCLE19591481.752665.265.6094%3.015.17172%1.62
291Tom FloresOAK196624141.713067.845.41145%4.585.09111%1.62
292Dan MarinoMIA19961791.893734.563.99114%2.413.41141%1.62
293Parker HallRAM19399130.692084.333.29132%6.257.66123%1.61
294Joe MontanaSFO198818101.803974.534.05112%2.523.63144%1.61
295Joe TheismannWAS198424131.854775.034.51112%2.733.94144%1.61
296Warren MoonMIN199533142.366065.454.12132%2.312.81122%1.61
297Chris ChandlerATL199825122.083277.654.23181%3.673.2789%1.61
298Daryle LamonicaOAK197218121.502816.414.64138%4.274.98117%1.61
299Jay SchroederRAI19901992.113345.694.37130%2.693.34124%1.61
300Danny WhiteDAL198122131.693915.634.26132%3.324.05122%1.61

• Mat

I noticed that a significant amount of these (especially in the top-10) are significant career outliers. Now I’m trying to rectify that with an explanation.
Any ideas?

Probably because TD’s and especially INT’s are heavily influenced by randomness, so it’s not surprising to end up with a bunch of fluky seasons.

• Building upon this, remember also that there are a *lot* more player-seasons by mediocre-to-bad quarterbacks than there are by historically great ones. So even if elite quarterbacks are much, much more likely to do well in this metric, we should expect to see a lot of weird names just because the standard deviation is huge and the base rate of mediocrity is so much higher.

I’ve always thought the threshold to qualify for rate stats is too low. Would prefer 20 attempts per game instead of 14.

• Joe Montana – 9 top 300 seasons
Peyton Manning – 8
Fran Tarkenton – 7
Tom Brady, Aaron Rodgers, Steve Young – 6

34 players earned half of all the top seasons. There are 65 players on the list just once, and there are 67 seasons from the top 11 players on the list. That’s interesting, I guess.

• Hey Chase, if you want to milk one more post out of this, you could always do the biggest overperformers in TD to INT differential instead of ratio, which should reward volume and weed out the Huards and Foleses to a large extent.

As a for-instance: at the 2006 league-average TD rate, Huard would have had 9.49 TDs and 7.44 INTs, for a differential of +2.05. Instead, he had 10 and 1 for a differential of +10. This means his differential was 7.95 above what we would have expected based on his volume. Do the same thing for 2010 Tom Brady. We’d expect 21.99 TDs and 13.68 INTs, for a differential of 8.31. Instead, he had a differential of 32, making him +23.69 over expectations. 2013 Peyton Manning, based on his massive volume, would check in at +32.87 over expectations.

• If you wanted to be *REALLY* shameless, you could then follow up that follow-up with career differential over expectation, basically just a sum of everyone’s single-season totals. That’s the advantage of counting stats over rate stats.

I’m on board with this idea. Differential makes way more sense than ratio, and does a far better job of mitigating outliers. Also think the career numbers would be interesting.

• Tom

Now that we’re locked in to looking at TD/INT, why not try another method? I think this looks pretty good.

• Richie

Not sure if it would be any different, but another method would be to add league average TD rate and INT rate to a players’ total to get them to 500 pass attempts.

So you would add 10 TD’s and 7.8 INT’s for Huard to give him a 21/8.8 season.

• Would you treat each INT as 2.25 times as valuable as each TD? I think that makes more sense than just using a raw differential.

I calculated every player’s relative TD and INT% and multiplied that by their attempts, effectively arriving at marginal touchdowns and marginal interceptions (like I did the week I took over FP). Then I multiplied MTDs by 20 and MINTs by 45, basically just using the ANY/A weights, to come up with a differential score.

For example:
Brady’s 2007 rates as the greatest ever. His 8.65 TD% and 1.38 INT% on 578 passes gave him 25.7 marginal TDs and -10.1 marginal picks. That’s 514 points for touchdowns and -456 points for interceptions. The differential is +970 points.

Here’s the top 20 careers by that method (no prorating or volume adjustments):

https://pbs.twimg.com/media/CqATaJRWgAAEnZT.jpg

Of all the methods proposed over the last few days, I like this one the best because it doesn’t have any obvious biases. I also think it highlights the limitations of TD/INT, as we know Roman Gabriel is not a top 10 QB all time, nor are McNabb, Gannon, and Lomax top 20. The INT avoiders are consistently overvalued by TD/INT, regardless of era.

• Josh Sanford

There are some incredibly intelligent and rigorous methodologies proposed by the readers for eliminating the aberrant seasons. For me, I’d like you to just ‘literally’ remove the aberrant seasons: If you don’t make the list twice, then you don’t make the list at all. And now the Top 300 Seasons just contains 235 entries.

• Sal Cacciatore

In baseball, strikeout-to-walk ratio is kind of falling out of favor, getting superseded by K-BB% (strikeouts minus walks per plate appearance). Using plate appearances, rather than walks, as the denominator makes it more effective and predictive of future success (http://www.beyondtheboxscore.com/2012/11/25/3686732/stop-using-k-bb) .

Might TD% – INT% would show a similar improvement over TD/INT?

• I think you need to provide some weight to INTs to make that work; an INT is perhaps 2.25 times as significant as a TD.

• WR

Chase, could you use this method to produce career totals?

• WR

The most “balanced” entries on this list, i.e. at least 140 for both TD+ and INT+, minimum 350 pass attempts

04 Manning 218 TD+ 150 INT+
11 Rodgers 208 TD+ 242 INT +
07 Brady 207 224
94 Young 199 146
13 Manning 185 176
96 Favre 180 TD+ 142 INT+
12 Rodgers 165 180
76 Bert Jones 165 180
98 S Young 165 141
10 Brady 164 342
89 Montana 164 183
98 Testaverde 163 TD+ 197 INT+

• Anders

You forgot McNabb in 2004 with 146% TD and 177% int

• WR

Ya it wasn’t a complete list. Here are the 12 best scores with at least 140 for both. I like this list because it weeds out guys like Foles and DeBerg.

10 Brady 164 TD+ 342 INT+
11 Rodgers 208 242
07 Brady 207 224
14 Rodgers 161 260
09 Favre
92 Young
04 Manning
13 Manning
98 Testaverde
89 Montana
12 Rodgers
94 Young

McNabb makes the list if you make it longer.

• Douglas Bath

Aaron Rodgers makes taking care of the football a top priority. I mean… he has more MVP trophies than career pick 6’s.