Rocky Marcinao fought 49 times in 8 years.
Muhammad Ali, by comparison, fought 61 times in 18 years (not counting the 3 year layoff).
Larry Holmes fought 50 times in 13 years (up until his 2nd loss to Spinks and first retirement).
Evander Holyfield fought 56 times in 27 years.
MIke Tyson fought 56 times in 16 years (not counting the 4 year layoff 1991-1995)
Lennox Lewis fought 44 times in 14 years.
Vitali K fought 47 times in 16 years.

Deontay Wilder fought 32 times in 6 years--about the same rate as Tunney