The batting age curve

“An age of around 32 is reckoned to be the best for batsmen,” wrote S Rajesh and Shiva Jayaraman for The Cricket Monthly last year, “but in the current decade, older has definitely been better.”

The records of Misbah and Sangakkara, among others, have certainly helped challenge the received wisdom that test batsmen peak in their early thirties. However, we shouldn’t let the few get in the way of the many – at what age does a typical batter peak?

The easy option would be to look at batting average by age group, but this is inherently biased. We know that if a batsmen is 35 years old and playing, it’s probably because he’s sustaining an impressive run of results (think Mike Hussey), whereas a 25-26 year old could be anyone from James Vince to Kane Williamson. Indeed, in the postwar era over-34s average 40.61 while 25-26 year olds average 36.02 – but this doesn’t necessarily mean a batsman will be better at 34+ than in his mid-twenties.

Instead, we can look at two different selections of individuals across different age groups (under-23s, 23-24s etc):

1. The best 75 batsmen* in each age group  in postwar history
2. The 27 postwar batsmen who have played in each group

Plotted together like so:

The green line averages the career trajectories of batsmen who showed tremendous longevity, playing test cricket before they turned 23 and after they turned 35. Collectively their batting didn’t really take off until their late 20s, with a gradual but significant decline to retirement.

The blue line suggests batters can reach their peak much earlier. Unlike the green line, there are different selections of players within each age group. Graeme Smith, for example, was one of the top 75 batsmen in the under-23, 23-24, 27-28 and 31-32 age groups, but not the 25-26 or 29-30 age groups**. Gautham Ghambir was the 10th-best 27-28 year old, but failed to make any other group.

This creates a slight distortion in the data, but gives us a sense of what each age group is at least capable of.

The most important finding, however, is that both groups peak in the 29-30 year old bucket, with a decline of 20-25% to follow. This is perhaps slightly earlier than received wisdom suggests.

This isn’t particularly groundbreaking in and of itself, but it’s useful information for national teams in their succession planning. Perhaps, for example, the need for Alastair Cook’s (32 in December) replacement is sooner than envisaged.

Meanwhile, while we salute the likes of Misbah ul-Haq, he very much is the exception to typical the age curve.

*Chosen somewhat arbitrarily, though given the limited number of under-23 batsmen in the sample, picking the top 75 meant we at least weren’t selecting bowlers who had played the requisite innings

**Ricky Ponting, incidentally, was the only batsman who was in the top 75 in each age group; validation of his remarkable consistency. Kallis, Tendulkar, Sangakkara and Sobers made the top 75 in 7 of the 8 age groups.