The Hundred 2021

Batting and Bowling Impact Indices

The Statistics Logistics sub-group of the ACS, chaired by Andrew Hignell, has considered the matter of ranking the impact of batsmen and bowlers in the new Hundred competition by a statistic that reflects more accurately their value than the pure traditional batting average does. A member of the sub-group, Ric Finlay, after some modelling, presented the case for using the geometric mean of the batting average and strike rate (measured in runs per hundred balls) for batsmen, and the geometric mean of the bowling average and economy rate (measured in runs conceded per 100 balls) for bowlers. For batsmen, it appears to satisfy the twin aims of batting for as long as possible in an innings limited by the number of balls bowled, and scoring at a competitive rate at the same time. For bowlers, the twin ambitions of taking wickets and denying runs to the batsmen are satisfied.

Batting Impact, BtI = √((Runs/Dismissals)*(Runs*100/Balls Faced))

Bowling Impact, BwI = √((Runs Conceded/Wickets)*(Runs Conceded*100/Balls Bowled))

It was felt that these formulae were effective in quantifying and ranking the contribution of each player over a period of a season, or part-season. The tables that appear here for both the Men’s and Women’s Hundred competitions rank players by BtI and BwI respectively.


Analysis of Powerplays