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.

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

This means that Team 2 just has to match the average run rate achieved by Team 1 in the overs it has available. 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, Team 2's new target is (5 x 25) + 1 = 126.

This formula can alternatively be written as:

In other words, the target is reduced in proportion to the loss in overs. Using the same example as above, with this formula the new target for Team 2 is (250 x 25/50) + 1 = 126.

Very frequently the ARR method alters the balance of the match, usually in favour of the team batting second. This is because:

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