Last month at the NFL's annual meeting, Bill Belichick was asked why he still coaches.

"I just enjoy it. I don’t know why. I just do," he said, electing to pass on a more detailed response that probably would have included his thirst for competition and passion for the game of football.

A day like today, with Belichick turning 62, sparks the question that is sometimes asked in New England: How much longer will Belichick feel that way? In the documentary "Bill Belichick: A Football Life," Belichick said he didn't plan to coach into his 70s like former Buffalo Bills coach Marv Levy. That is still eight years away.

Belichick is the third-oldest coach in the NFL, behind Tom Coughlin and Pete Carroll, and when considering any top coaches ranking, the three would almost certainly be near the top.

Breaking down the head coaches by age:

Born in the 40s

Giants' Tom Coughlin -- 67 (8/31/46)

Born in the 50s

Seahawks' Pete Carroll -- 62 (9/15/51)

Patriots' Bill Belichick -- 62 (4/16/52)

Cardinals' Bruce Arians -- 61 (10/3/52)

Lions' Jim Caldwell -- 59 (1/16/55)

Broncos' John Fox -- 59 (2/8/55)

Bears' Marc Trestman -- 58 (1/15/56)

Vikings' Mike Zimmer -- 57 (6/6/56)

Rams' Jeff Fisher -- 56 (2/25/58)

Chiefs' Andy Reid -- 56 (3/19/58)

Buccaneers' Lovie Smith -- 55 (5/8/58)

Bengals' Marvin Lewis -- 55 (9/28/58)

Falcons' Mike Smith -- 54 (6/13/59)

Born in the 60s

Colts' Chuck Pagano -- 53 (10/2/60)

Dolphins' Joe Philbin -- 52 (7/2/61)

Panthers' Ron Rivera -- 52 (1/7/62)

Titans' Ken Whisenhunt -- 52 (2/28/62)

Ravens' John Harbaugh -- 51 (9/23/62)

Jets' Rex Ryan -- 51 (12/13/62)

Packers' Mike McCarthy -- 50 (10/10/63)

Eagles' Chip Kelly -- 50 (11/25/63)

49ers' Jim Harbaugh -- 50 (12/23/63)

Saints' Sean Payton -- 50 (12/29/63)

Bills' Doug Marrone -- 49 (7/25/64)

Cowboys' Jason Garrett -- 48 (3/28/66)

Jaguars' Gus Bradley -- 47 (7/5/66)

Browns' Mike Pettine -- 47 (9/25/66)

Redskins' Jay Gruden -- 47 (3/4/67)

Texans' Bill O'Brien -- 44 (10/23/69)

Born in the 70s

Steelers' Mike Tomlin -- 42 (3/15/72)

Chargers' Mike McCoy -- 42 (4/1/72)

Raiders' Dennis Allen -- 41 (9/22/72)