Weighted averages were created by England's analysis team in 2011, as a way of revealing more than traditional averages. Initially, the weighted averages for players were just calculated by specific requests. From 2016, weighted averages - for both first-class and Test cricket - have appeared automatically in the England selectors’ app after each match. Since Ed Smith became England’s national selector this summer, weighted averages have become the default way by which players are filtered on the selection app, emblematic of their growing importance.

In the interviews to be new England national selector this year, candidates were asked to make a presentation on whether selection is an art or science. It has always been both. The embrace of weighted averages is not at the expense of character assessment and cricketing judgement; it merely reflects a belief that, if numbers are to be used as part of the process it makes sense to use the best possible ones.

Weighted average is not a perfect metric - but nor does it need to be. To be of use, it simply needs to be better than old-fashioned numbers. England believe that weighted averages more fully capture what matters in a player’s performance, just as the Oakland Athletics recognised that on-base percentage was a better way of measuring a player’s performance than the traditional baseball batting average. Others are also trying to use averages in a more enlightening way: Dan Weston, a professional gambler and data analyst who has consulted for first-class sides, has developed a similar system.

The calculation of weighted average is actually fairly simple. The metric takes into account the quality of the batsmen or bowlers faced - and, for bowlers, the quality of the batsmen they dismiss - whether the match was high or low-scoring, and if the player was at home or away. So a batsman making 80 will get far more credit when it is top score in a match - as Buttler's unbeaten innings in the second Test against Pakistan was - than when it comes during a high-scoring draw. This summer, Keaton Jennings has a Test batting average of 20, yet a weighted average of 33, showing how the numbers adjust for a summer in which ball has dominated bat - and that, for all his uncertainty, all other openers have struggled too.