Deshaun Watson was spectacular in 2017. Every football fan, analyst, team, and player remembers his insane rookie season because he did things like this:

As incredible as Watson was at dipping out of sacks, turning negatives into neutrals, turning negatives into positives, picking up chunks on the ground, throwing short passes with anticipation, and slinging it deep, Watson’s best skill in 2017 was much simpler than that. It was throwing touchdowns. Watson couldn’t stop throwing them. Even his interceptions turned into touchdowns.

Watson started six games as a rookie. In those six games, Watson threw 204 passes, completing 126 of them (61.76%) for 1,699 yards and 19 touchdowns. Most importantly Deshaun Watson had a touchdown rate of 9.3%.

Think about that number for a second. That 9.3%. 9.3%! Since 1990, there have been 942 seasons in which a quarterback has thrown a minimum of 200 passes. From Peyton Manning throwing 55 touchdowns in 2013 to Bobby Hoying throwing 0 touchdowns in 1998 on 224 attempts, there have been only two quarterbacks who have had a touchdown rate greater than 9.0% in a season. Watson and Peyton Manning. That’s it. Aaron Rodgers narrowly missed the mark with a 8.96% touchdown rate in 2011 when he threw 45 touchdowns on 502 attempts. So close.

Going back to the dawn of football, the pebble of Makapangst Manuport of football statistics, a 9.0% touchdown rate of a minimum of 200 pass attempts has happened only sixteen times. Twice since the turn of the millennium, seven times in the 1940s, once in the 1950s, five times in the 1960s, and once in the 1970s. Watson did something that hasn’t been done since Peyton Manning did it in 2004; Manning did something that hadn’t been done since Ken Stabler in 1976, who did something that hadn’t been done since Len Dawson did it in 1962.

The highest touchdown rate in the history of football belongs to Sid Luckman, who threw 28 touchdowns on 202 attempts; that comes out to a rate of 13.9%. Frankie Albert is the only player who pulled the feat off in consecutive years. Albert and Len Dawson are the only ones on this list twice. Ken Stabler’s 1976 season is particularly impressive considering when he did it and the inability of anyone to do it again for 28 years.

Despite changing the game, what helmets were made out of, or the days the games were played, all of these QBs saw their touchdown rate dip the following season. Combined these quarterbacks had an average touchdown rate of 10.0; the following season, their average touchdown rate was 6.3%, an average difference of 3.7%.

The smallest dip was Luckman, who went from 11.0% to 10.4%, but he fell all the way to 3.9% the season after he did it again. The largest drop was Adrian Burk, who went from 10.0% to 3.9%. Manning, the last one to do it, saw his touchdown rate drop from 9.9% to 6.5%, a 3.4% that was slightly above the average change. Even the second greatest quarterback of all-time nestled among a bunch of WW2 era quarterbacks saw his touchdown rate drop. That’s the key. These +9.0% seasons are special and unique. They aren’t something generally sustainable in the future.

Now, 1942 was a long time ago. To change the parameters to fit the modern age the touchdown rate has to drop. At a drop from 9.0% to 8.0%, from 1990 on, only eight quarterbacks were able to complete this extraordinary achievement. Manning, Watson, Aaron Rodgers, Tom Brady, Nick Foles, Kurt Warner, and Randall Cunningham.

Like the previous set of players, they too were unable to throw touchdowns at the same elevated rate the following season. The average touchdown rate dropped from 8.73% to 4.9%, a difference of 3.86%. The difference drops to 3.0% if Tom Brady’s Bernard Pollard knee-torn season is removed. Like the previous list, there were players who saw significant drops. Manning was mentioned earlier. Foles dropped from 8.5% to 4.2% (-4.3%). Cunningham dropped from 8.0% to 4.0% (-4.0%).

This is an elite company to be in. There are four Hall of Famers on this list, three of the greatest quarterbacks of all time, an unlikely Super Bowl MVP, and a quarterback who was named to four Pro Bowl teams and was a first team All-Pro once. Among this company, Watson leaps out. For one, he threw only 204 passes. He hit 9.0% in a small sample size. Foles is at the bottom of this list in attempted passes at 317, but the rest averaged 526 attempts and threw a minimum of 400. Watson did the incredible in a small spat of games.

The other thing that stands out is the number of wins. Manning won 12 and 13 games, Warner won 13 games, Cunningham won 13 games, Foles won 8 games, Rodgers won 14 games, and Brady won 16. These 8.0% touchdown seasons end with teams clinching one seeds and going on deep playoff runs. Houston never got this chance when Watson went down with a knee injury with two months of the 2017 left.

Even the all-time great quarterbacks were unable to replicate what they did the previous season. None of these quarterbacks were able to repeat what they did the following season, and Manning was the only one to do it twice during his entire career. These are special seasons that rarely occur.

If this list is expanded to 7.0%, more names appear. Since 1990, 23 quarterbacks have a touchdown rate of 7.0%. The list expands by 15.

These quarterbacks aren’t special. They also couldn’t repeat what they did the previous year. The average difference in touchdown rate was 2.7% without Brady’s injury-ruining year; it’s 2.9% with it included. The biggest difference between 7.0% and 8.0% is the rate is much more attainable. Three quarterbacks were able to get close to matching what they did the previous season. Brady dropped from 7.3% to 6.4% in 2011. Brees dropped from 7.0% to 6.4% in 2012. Brett Farve had the most consistent touchdown rate of anyone; his dropped from 7.2% to 6.8% in 1997.

Watson is also the youngest quarterback on this list at 22 years old. Foles pulled it off at 24, Carson Wentz did before he was also injured at 25 years old, and Ben Roethlisberger was 25 when he did it. A couple others had just entered the prime of their career. Eight of these quarterbacks were 27 or younger, and these younger quarterbacks’ touchdown rates dropped by 2.8%. None of the quarterbacks who reached this mark at this age were able to break 7.0% again. Both Watson and Wentz will have the rest of their career to try and climb that mountain again. On the other end of the list are older quarterbacks like Chris Chandler, Tony Romo, and Steve Young who were never able to do it again. Chandler’s 1998 campaign is the football version of Brady Anderson’s 50 home run season.

This isn’t to say Watson is going to be a disaster next year, or that he will only be a good quarterback. To do what he did at all is spectacular. It’s one of the most incredible things to happen in the history of the NFL. It is certain, however, that Watson isn’t going to throw a touchdown on 9.3% of his passes again. If he drops by the likely average of 3.0% over the course of 500 attempts, it still comes out to a spectacular 31.5 touchdowns over the course of a season. If he drops to the average touchdown rate since 1990 over the course of 500 attempts, it comes out to 20.6 touchdowns in a season.

My best guest is that Watson ends up somewhere between the two. There’s nothing to indicate that Watson won’t be a great quarterback for the long-term. Unless he’s an outlier like Nick Foles, the numbers actually point to him being a perennial Pro Bowl quarterback. It’s an incredible list to be a part of. But this is still unknown. Watson did what he did over 204 attempts in a brand new offense that caught defenses off guard. He coming off major knee surgery. Historic touchdown rate aside, he also threw an interception on 7.19% of his passes. My brain and heart tell me Deshaun Watson is a franchise quarterback, but the future is murky. He had an all-time great season. He did something that had only been done twice since 1990, nine times in the history of football. He did it all in his rookie year.

Deshaun Watson won’t have a similarly insane touchdown rate next year. He probably never will have another for the rest of the career. Because of this, the data has me skeptical that Watson is going to play like the superstar he was in 2017 during the 2018 season.