Table 2
Summary of change in length of career and bouts across eras
Fight era
N
References
Average career length (years)
Range (years)
Average bouts
Range
1900–1955
254
3, 10, 15, 16
19
3–22
336.5
<50–700+
1950–1995
77
17, 18, 19
9.6
1–22
39.6
0–122
2000 – present
295
9, 20
5
1–32
13.3
1–138