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One of the biggest influences to fantasy football scores is a touchdown. Plenty of randomness goes into a touchdown from a defensive turnover creating a short field, jump ball in the end zone, pass interference penalty to even a tipped pass or garbage time drive. The Red Zone channel parks most of their coverage inside the 20-yard-line for a reason: touchdowns live there. The term touchdown regression has been around awhile. Back in my profootballfocus.com writing days, I scoured nearly every offensive statistic looking for the best regression outliers from year to year. While there were some categories fighting for second place, touchdown rate was annually at the top, both in its strength of regression and in bottom-line fantasy football impact. With the NFL Draft in the rear-view mirror, let's look at touchdown regression for the quarterback position in 2016:

Sample Size: 236 quarterbacks from 2005-2015

Criteria: 250+ attempted passes in both the test season and the following season

THE TOUCHDOWN DATA

Overall, these 236 criteria-fitting quarterbacks averaged a 7.5% touchdown rate (on their completed passes)

Using a big picture lens, the average drop of 3.0% for a decent volume of completions is in the range of 7-10 touchdowns. This is a huge correction and arguably the single most important regression trend to notate for the following year's drafts and player valuations. On the flip side, the low touchdown rate group's boost was as stark and adding 5-10 touchdowns to their total turns them from and afterthought or fantasy dud back to matchup QB2 or better the following season. Anything over 80-85% regression is a strong trend. Adding these players to target and avoid lists can clarify draft values for the following year based on expected opportunity and price.

In 2016, we saw the high touchdown group log a perfect 5-fo-5 regression downward, including Cam Newton's -4.8% dip (35 touchdowns to 19), Russell Wilson slipping -4.4%, Carson Palmer down -3.1%, Blake Bortles dropping 3.6%, and Andy Dalton plummetting -4.9% and losing seven scores.

For the low touchdown rate crew, last year had none of the qualifiers from 2015 log more than 250 attempts to fit the sample in 2016.

2017 QUARTERBACKS: MOVING UP

Let's start with the low touchdown rate quarterbacks from 2016. Remember, the historical data is based on the quarterback logging at least 250 attempts for a second straight season.

carson wentz, 4.2%

Wentz had a woeful set of weapons as a rookie, but Alshon Jeffery and Torrey Smith immediately bolster the targets, including incumbents Jordan Matthews and Zach Ertz. Similar touchdown rates have risen by 2.1% historically, which would be a net gain of 7-10 scores for Wentz, pushing into the mid-20s.

alex smith, 4.6%

The Chiefs drafted Patrick Mahomes, but Smith is likely to remain the starter for all of 2017. Kansas City did not add any notable pass-catchers outside of two-way rookie running back Kareem Hunt this offseason.

Joe Flacco, 4.6%

Baltimore lost Steve Smith to retirement and 2017 is a pivotal one for Breshad Perriman. Mike Wallace and a bevy of tight ends round out Flacco's main targets. Flacco has hovered in the 5-7% rate for much of his career with 2016's 4.6% mark the lowest of his career. 2013 was Flacco's second-lowest rate of touchdowns at 5.2% and the following year he added eight touchdowns, up to 7.8%.

andy dalton, 4.9%

Dalton was one of the interception regression calls from 2015, hitting well as he cut his rate by more than half in 2016. Touchdowns are the regression to watch for Dalton in 2017 after tossing just 18 scores. Cincinnati added John Ross in the first round and elite receiving back Joe Mixon in Round 2. Health with A.J. Green and Tyler Eifert are also paramount to Dalton having his full complement of weaponry. 2016 was Dalton's first season with less than a 6% touchdown rate. 2014 was the most similar to his 2016 year - the following season Dalton added six passing touchdowns.

2016 QUARTERBACKS: MOVING DOWN

Now, let's hit on the strongest regression group from 2016 - the high touchdown rate. Previously only 2011-2012 Drew Brees beat the regression with an equal or better touchdown rate the following season from this subset. Five quarterbacks in 2016 made the hot list to track for 2017:

matt ryan, 10.2%

Kyle Shanahan is gone and a few of the ancillary speed-demon targets as well for Ryan and the Atlanta pass game. This was Ryan's first season above 8.4% in his career and first above 32 passing touchdowns. Ryan is also on the interception regression watch list, making him one of the diciest investments at the quarterback position this season to expect a repeat performance.

aaron rodgers, 10.0%

Rodgers, like Tom Brady, has a high career touchdown rate. However, his biggest seasons have included regressions the following year like any other quarterback. Rodgers' big 11.1% rate in 2014 including a drop to 8.9% (seven touchdowns lost) in 2015. Expect at least 3-5 touchdowns off Rodgers' total if history is any indication for 2017.

tom brady, 9.6%

Brady is coming off his highest touchdown rate since 2011. Even though his rate is likely to decline, Brady missed games in 2016 and his raw total should increase from 28 a year ago. More regression-worthy is his 1.4% interception rate, by far the lowest of his career, which is primed to triple based on his historical track.

Philip rivers, 9.5%

Rivers logged his second-highest touchdown rate of his career in 2016, only eclipsed by his breakout 2008 season. Rivers is the best bet to come close to repeating his strong 2016 showing of this list with Keenan Allen missing most of 2016 and set to return, drafting Mike Williams at No.7 overall in this year's draft, and Antonio Gates still around to work the end zone (plus Hunter Henry developing into his second season). Rivers' toolbox is loaded and something in the 8-9% range is projected for 2017.

marcus mariota, 9.4%

Mariota is on the upper touchdown rate group track through two seasons, hitting 8.3% and 9.4% respectively. Mariota, like Rivers, adds a top receiver from the 2017 rookie class in Corey Davis to an otherwise unspectacular group of weapons. Mariota has also yet to throw more than 451 times in a season.

THE INTERCEPTION DATA

The interception regression trends are even stronger than touchdowns. High interception rates result in either a quarterback being yanked before reaching the 250-attempt threshold the following year or a marked improvement. 

2017 QUARTERBACKS: MOVING UP

Let's start with the low interception rate quarterbacks from 2016. Remember, the historical data is based on the quarterback logging at least 250 attempts for a second straight season.

TOM BRADY, 1.4%

Brady has a been a low interception rate quarterback over his career, and managed to be an outlier to this strong regression trend last year. After serving his suspension, Brady dropped his 3.2% rate from 2015 to a miniscule 1.4% last year on 432 attempts. The second-lowest rate of Brady's career was 2.4% in 2010. The following season it bulged to 5.7% and added eight interceptions to his tally in 2011.

dak prescott, 2.9%

Prescott was a well-controlled rookie, leading Dallas into the playoffs with a strong run game and many defined throws in the pass game. Without any career trends or averages, Prescott is a wildcard in terms of career regression. However, sub-3% interception rates have more than doubled the following season on average, including years by Aaron Rodgers and Tom Brady in the past. Prescott may be a successful long-term NFL starter, but the odds are strong for him to approach (or surpass) double-digit interceptions in 2017.

derek carr, 3.0%

Carr has had a better than NFL average interception rate through his three NFL seasons. However, 3.0% is by far his best to-date. Like Prescott, Carr falls in the zone where doubling an interception rate is far more common than a repeat performance. Expect 10-15 interceptions from Carr more times than single digits this coming season.

sam bradford, 3.2%

Bradford, like the Alex Smith mold, has been one of the lower interception rate quarterbacks over his career. Bradford logged a 3.6% season back in 2011, only to balloon to 5.8% the following year. Bradford is likely to see his five interceptions from 2016 shift to 8-12 if he plays a full season.

aaron rodgers, 3.3%

Rodgers, like a Tom Brady, is one of the all-time greats with a tremendous track record of high touchdown and low interception rate seasons. However, Rodgers' sub-4% interception rate seasons have risen in 3-of-4 previous occasions. Rodgers is obviously one of the best bets to repeat a low interception campaign on this list with now six straight years of single digit interceptions and three straight years of sub-4% rates.

tyrod taylor, 3.6%

Taylor has a smaller sample as a starting quarterback, but both of his seasons include sub-4.5% interception rates. Taylor is on the hot seat with little allegiance from Buffalo's front office beyond 2017, making this a pivotal year to shape Taylor's future opportunities under center. Adding pro-ready Isaiah Jones as a Round 2 rookie receiver and a healthy Sammy Watkins will boost Taylor's chances to log single-digit interceptions for a third straight season.

2016 QUARTERBACKS: MOVING DOWN

Finally, here is the high interception rate group from 2016. Ben Roethlisberger was a notable hit from 2016, dropping his 10.7% rate to 7.2%, shedding three interceptions.

ryan fitzpatrick, 9.7%

Fitzpatrick is not projected to hit the 250-attempt threshold as the backup in Tampa Bay.

Ryan Tannehill, 9.4%

2016 was by far the highest interception rate of Tannehill's career. The previous high-water mark was 7.3% in 2013. DeVante Parker has plenty of buzz for a breakout season and Jarvis Landry, Kenny Stills, and newly added Julius Thomas form a strong reservoir of weapons for Tannehill to (finally?) hit his ceiling.

Philip Rivers, 9.2%

Rivers has had three previous seasons above 8% interceptions, all of which provided fantasy value to exploit the following season. Each of those occasions Rivers shed 4-5 interceptions the next year. Rivers has been in the higher band of interception rate for his career, but surpassing 20 interceptions as a locked-in starter like Rivers presents a buying opportunity in Y+1. Keenan Allen returning from missing most of 2016 with injury and drafting Mike Williams in Round 1 only aid Rivers' cause. 

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