Average Run Rate method

The Average Run Rate (ARR) method was a mathematical formulation designed to calculate the target score for the team batting second in a limited overs cricket match interrupted by weather or other circumstances. Often matches interrupted by weather would use Reserve Days, bowl outs, or were replayed on another date, but when that could not happen, the ARR method might be used instead.

The ARR method was used from the start of one-day cricket in the 1950s/1960s, until replaced by the Most Productive Overs method in the early 1990s.

Calculation

If an interruption means that the team batting second loses some of their overs, their target score is adjusted as follows.

${\text{Team 2's new target }}={\text{ (Team 1's Average Run Rate achieved}}\times {\text{Overs available to Team 2)}}+1.$

This means that Team 2 just has to match the average run rate achieved by Team 1 in the overs it has available. In other words, the target is reduced in proportion to the loss in overs.

For example, if Team 1 made 250 in their 50 overs, which is an ARR of 5 runs per over, and Team 2’s innings is reduced to 25 overs, the new target is (5x25)+1=126.

Notable matches decided by ARR

• England v Sri Lanka in the 1987 Cricket World Cup. England scored 296 from 50 overs, an ARR of 5.92. Sri Lanka's innings was reduced to 45 overs, therefore their target was 267 (5.92 x 45 = 266.4).