Most Productive Overs method

The Most Productive Overs (MPO) 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.

It was used from the early 1990s, when it replaced the Average Run Rate method, until the late 1990s.

MPO was used most notably during the 1992 Cricket World Cup, and the controversial effect of its application during the England v South Africa semi-final directly led to the development of the current method, the Duckworth-Lewis method.

The Average Run Rate method was replaced in 1991 by the Most Productive Overs method, developed by Australians after the third 1989 World Series final between Australia and the West Indies. Chasing Australia's 226/4 off 38 overs, the West Indies needed 180 off 31.2 overs. Rain stopped play for one hour and 25 minutes, and under the average run-rate method, the revised target was 61 runs off the 11.2 overs that remained. The West Indies won the match and the competition with 4.4 overs remaining and eight wickets in hand. Australian fans booed this unsatisfactory conclusion, which was criticised by the media and Australia's captain Allan Border. In this match, the Duckworth-Lewis method would have increased the West Indies' target to 232 to take into account a two-hour rain delay during Australia's innings, and then revised the target to 139 after the second interruption.

If an interruption means that the innings of the team batting second is reduced to a total of X overs, their target score is adjusted as follows:

Whereas the Average Run Rate method heavily favours the team batting second ("Team 2"), the MPO method heavily favours the team batting first ("Team 1"). This is because it keeps the best parts of Team 1's innings, and requires Team 2 to match this throughout the whole of their innings. It penalises Team 2 by ignoring their best efforts during Team 1's innings. The least productive overs may well have been maiden overs, so Team 2 may therefore have to match Team 1's score but with fewer overs.

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