In the span of just 14 months, the Chicago Bears have transitioned from the league’s oldest roster to one of the youngest.

While the Bears' evolving youth moment delivered only six wins in 2015, coach John Fox is confident the dramatic roster turnover is a clear sign of progress.

“We were the oldest team in the NFL roster-wise, and now we are one of the top two or three youngest,” Fox said on ESPN’s NFL Live. “It’s a transformation that takes time. Obviously a 6-10 record is not what we are looking for, but we saw improvement both in the culture and in the way the guys played. I think with more injections of talent we are going to get there.”

Since Fox and general manager Ryan Pace took control of the organization, the Bears systematically waived goodbye to numerous players in their 30's, including Roberto Garza, Jared Allen, Lance Briggs, Charles Tillman, Tim Jennings, Brandon Marshall, Jermon Bushrod and Matt Forte.

The Forte move, in particular, highlighted the Bears’ philosophy of skewing younger whenever possible. The club failed to even make an offer to keep Forte, who is the second-most productive tailback in franchise history. Forte quickly signed a three-year contract with the New York Jets that included $9 million in guarantees.

“Matt is a great guy, a great Bear, and a great tribute to our organization,” Fox said. “But we felt really good about our younger players like Jeremy Langford, who we drafted the year before, Ka’Deem Carey and Jacquizz Rodgers. Those are guys we felt could carry that position. It was more or less getting draft picks and trying to improve our team. Going youthful.”

A quick glance of the Bears’ current offseason roster reveals only six players in their 30's: Robbie Gould (34), Jay Cutler (32), Antrel Rolle (33), Matt Slauson (30), Willie Young (30) and Zach Miller (31). Newly re-signed cornerback Tracy Porter turns 30 years old in August.