Carolina Panthers center Ryan Kalil laughs off the notion of a so-called sophomore slump among NFL quarterbacks.

Kalil lumps talk of a sophomore slump alongside such myths as the Sports Illustrated cover jinx, the bogeyman and Bigfoot.

“To me that’s stuff that all gets grouped in like the Madden Curse and all that,” said Kalil, referring to the bad luck that allegedly befalls those featured on the cover of the popular video game. “I don’t really pay too much attention to it.”

Neither should serious fans of the NFL.

According to data compiled by the Observer, the idea of sophomore slump is based more on fiction than fact – at least in recent years.

Since 2000, quarterbacks who started at least eight games in their rookie and sophomore seasons, on average saw statistical improvements in nearly every aspect of their game, the Observer found.

Completion percentages and touchdown passes were up during a quarterback’s second season; interceptions, sacks and fumbles were down.

So if Panthers quarterback Cam Newton, the AP Offensive Rookie of the Year in 2011, struggles in his second season, he will be breaking a statistical trend. As good as Newton was in his first season, former NFL quarterbacks say he should be better this year.

“Typically we see the most improvement – I’m talking across the board – from year 1 to year 2 in (offensive) systems,” said retired quarterback Rich Gannon, whose career spanned 18 seasons.

“Year 1 there’s a lot of new learning. There’s a lot of install. You don’t have the entire offense. You’re continuing to build and grow and develop a system,” added Gannon, a CBS analyst and host of a Sirius/XM NFL Radio show. “In year 2 you see the thing grow a little bit and expand. You see the quarterback get more comfortable at the line of scrimmage, change protections, audible. You see him not making the same mistakes he made his first season.”

Stability aids improvement

Newton set the bar high last season, breaking Peyton Manning’s single-season, rookie passing record with 4,051 yards and becoming the first quarterback in league history to finish with at least 4,000 yards passing and 500 yards rushing.

But Newton was not perfect. He threw 17 interceptions, was sacked 35 times and finished with a passer rating of 84.5, which was 15th in the league.

Recent history suggests Newton’s numbers will improve this season.

Of the 13 quarterbacks since 2000 who started at least eight games in their rookie and sophomore seasons, only two – St. Louis’ Sam Bradford and Atlanta’s Matt Ryan – saw a decrease in quarterback rating. Meanwhile, seven of the 13 saw a quarterback rating jump of more than 5 points.

Those same quarterbacks saw their completion percentage increase 2.4 percent and their passer rating increase more than 7 percentage points. They threw more touchdowns per game, completed 2.3 more passes per game and passed for an additional 20.8 yards per game, data show.

Meanwhile, their per-game average for interceptions, sacks and fumbles decreased.

“History shows there’s been situations (where second-year quarterbacks struggled) – the sophomore slump was created somehow some way, right?” former Panthers quarterback Chris Weinke said. “But I think the important thing when you’re talking about the quarterback position, the first year is always the toughest. You would think that second year, because of the experience, that you’re going to be better.”

“Now at that position, a lot more’s predicated on your supporting cast, too,” added Weinke, who runs the football division at IMG Academy in Bradenton, Fla., where the Panthers practiced this week. “And I think that’s the one thing that gets overlooked every once in a while.”

Gannon said another factor that gets overlooked is continuity in an offensive system.

Bradford, like Newton a No. 1 overall pick, was the league’s Offensive Rookie of the Year in 2010 when he threw for 3,512 yards and 18 touchdowns and guided the Rams to a six-win improvement.

After the season Rams offensive coordinator Pat Shurmur left to become Cleveland’s head coach, taking his West Coast offense – with a reliance on short, horizontal passes – with him. The Rams replaced him with Josh McDaniels, who installed a vertical passing attack with new terminology and new responsibilities.

Bradford’s completion percentage dipped from 60 percent to 53.5 and his six touchdown passes represented a third of his 2010 total.

“It’s two different worlds,” Gannon said. “It’s like learning a new language – new terminology, new verbiage. You call protections differently, different concepts in the passing game.”

Bradford, who missed six games with a high ankle sprain last season, is working with his third offensive coordinator in as many years this season. Former Jets offensive coordinator Brian Schottenheimer joined new coach Jeff Fisher’s staff in St. Louis.

Newton can relate. With stints at three colleges – Florida, Blinn Junior College and Auburn – Newton was learning his fourth offensive system in four years as a rookie.

It looked like he might be working with a different playcaller again when Panthers offensive coordinator Rob Chudzinski interviewed for three head-coaching positions during the offseason. But Chudzinski missed out on the jobs, much to the relief of many in the Panthers’ organization.

“The good thing about Cam is that he didn’t lose Chudzinski. That would have been a significant loss,” Gannon said. “Now you have to start over again. You’ve got a new coordinator, new play-caller. You’ve got to get a comfort for each other. And that trust factor between that coordinator and quarterback is absolutely critical.”

Sophomore surge

With more single-sport training and passing camps for young quarterbacks and the explosion of spread offenses at the high school level, NFL quarterbacks are more prepared than their predecessors when they arrive.

The five rookie quarterbacks who will start Week 1 are the most since at least 1950. There were two last year – Newton and Cincinnati’s Andy Dalton, who led the Bengals to the playoffs in his first season.

Jon Gruden, the former Oakland and Tampa Bay coach, is floored by the wave of NFL-ready quarterbacks.

“One of the most astounding statistics that I’ve seen in football in the last 25 years is the amount of young quarterbacks that are now playing early, but playing well,” Gruden said.

Even with that readiness as rookies, data shows that the majority of quarterbacks take another step their second seasons.

Baltimore’s Joe Flacco, the only quarterback in recent years to start all 16 games in his rookie and sophomore seasons, increased his rating 8.6 percentage points from his first to second year. He improved in nearly all areas, such as completions per game (+3.63), yards per game (+40.13) and touchdowns per game (+.44).

Of the quarterbacks who started at least half the games during their rookie and sophomore seasons, Tampa Bay’s Josh Freeman saw the largest increase in quarterback rating. During his rookie season, Freeman’s rating was 59.8. His quarterback rating was 95.9 his second season.

Increases were less pronounced for quarterbacks who did not start at least eight games their rookie year, but played the bulk of their second and third seasons. Those quarterbacks (seven since 2000) averaged a quarterback rating increase of just .66 percentage points.

Among them, the Bengals’ Carson Palmer was the biggest winner, increasing his rating nearly 24 points. Oakland’s JaMarcus Russell was the biggest disappointment. His quarterback rating dropped more than 27 points from his second to his third season.

Normal offseason could help

Analysts say the success of Newton and Dalton last season is even more impressive considering neither had the benefit of a normal offseason program. Because of the lockout, the players could not train at their facilities and there were no OTAs or minicamps to begin learning the offense.

Newton trained at IMG with Weinke for part of the lockout. They worked from the Panthers’ playbook, using Chudzinski’s terminology – from the call in the huddle to the cadence at the line of scrimmage.

Still, Weinke expects to see Newton improve following a traditional offseason.

“If there were any question marks, they would be going into his rookie year with the lockout (and) no offseason,” Weinke said. “He defied the odds, to say the least. But I think now he’s more comfortable with a whole year under his belt, then with a whole offseason, as well as more comfortable with the players around him.

“We should anticipate, but never assume, that his second year should be better than his first year.”

Newton has the Gatorade and Under Armour commercials and the flash of an “entertainer and icon.” But he also has the desire to keep improving, according to Chudzinski.

“Going back to when we first started back in OTAs, you look at Cam and he’s hungry to improve and get better,” Chudzinski said. “Everything from mechanics and drops and then reads and understanding the offense, getting the ball out and making the kind of decisions that you want him to make. It’s not just one area you’re looking at for improvement.”

Newton most wants to improve the Panthers’ six-win total from 2011.

Dan Marino played in his only Super Bowl during his second season. Ben Roethlisberger, at 23, became the youngest quarterback to win a Super Bowl when the Steelers beat Seattle during the 2005 season.

Newton has hinted that his expectations for this season include the Super Bowl, saying no one sets the bar higher than himself and calling Kalil his “hero” for his Super Bowl ad in the Observer.

“So many people still have expectations, feel a certain way about me. But I don’t think any of them ever will be as high as mine. I’ve said that once, and I’ll say it again,” Newton said this week. “I’m not surprised by anything that I do. The only thing that surprises me is when I do not play to my potential.”