INDIANAPOLIS -- If the last 20 years have taught us anything, it's that the Cowboys are likely to disappoint in 2017.

It's not to be negative before a team has entered free agency or even drafted a single player. It's just important to remember that consecutive big seasons have been rare in Dallas.

Since 1996, the Cowboys have had six double-digit win seasons. The average win total the following year: 6.5. There's also that 12-year run since an NFC East team has won the division back-to-back years.

The usually positive-spinning Jerry Jones said Saturday that he thinks the Cowboys will be able to sustain last year's regular-season success, but the owner and general manager also has concerns.

"Nothing stands still," Jones said, "just by the mere fact that we are looking at what we are doing in free agency and the fact that, counting practice squad, I hope we add 12 to 13 players here out of this draft. How the quality of what we do here as well as these decisions we make in free agency ...

"Certainly we are challenged with our [salary] cap, but that's the way we do it. Those all are not substantive worries, but they are certainly concerns that we have to work on to do good."

Health is something Jones can't predict.

It was very good in 2014, terrible in 2015 and then outstanding in 2016, particularly on offense. Jones was quick to mention the overachieving defense Dallas had in 2014 and '16 when discussing the topic. An offense that took care of the ball and controlled the clock also played a significant role.

"All of those fundamentals are there," Jones said. "The swing years compared to the year before, the ones where we had the big down [years], those things weren't there the same in each year. We lost them the next year.

"We had [Tony] Romo one year and then lost him. And we couldn't have the kind of year we had with [DeMarco] Murray and a healthy Romo. I don't think it's really ambitious to think we can have the same makeup of our team offensively. I believe we are going to improve defensively. But I certainly think we can maintain where we are."

Jones is also banking on youth helping to break the up-and-down trend.

The Cowboys haven't been major players in free agency the last few years, so over half the roster should be made up of players they've drafted. Dak Prescott, Ezekiel Elliott, Zack Martin, Travis Frederick and Tyron Smith are all 26 and younger.

Defensively, DeMarcus Lawrence, David Irving, Anthony Hitchens and Byron Jones are under 25. Jones also hopes for a boost from last year's draft class, particularly Jaylon Smith, Maliek Collins, Charles Tapper and Anthony Brown.

"The youth, the inspiration, we benefited from that last year with the young guys," Jones said. "The anticipation of those guys getting better at key impactful positions ... you just feel good about the future."

Will that bright future pay dividends with another double-digit win total in 2017, or will Jones & Co. have to wait for a bounce-back year in 2018? The last two decades suggest it's more likely the latter.