Duckworth-Lewis-Stern method (DLS)

The Duckworth-Lewis-Stern method recalculates a fair target score when a limited-overs cricket match is interrupted and overs are lost, so the team batting second isn't penalized or advantaged simply by the timing of a stoppage. It replaces older, cruder approaches such as scaling the target by the ratio of overs remaining, which ignore how many wickets a team has in hand.

The method treats overs and wickets remaining together as a team's "resources" for scoring runs. Historical scoring data is used to build tables estimating how much of a team's resources are used up at any combination of overs bowled and wickets lost; the revised target is set proportionally to each side's resource percentage at the point of interruption, rather than a simple runs-per-over reduction. It was developed by statisticians Frank Duckworth and Tony Lewis and adopted by the ICC in 1999, then recalibrated by Steven Stern in 2014 using a wider dataset, which added the "Stern" to its name.

Analysts and broadcasters use DLS-adjusted par scores to track a chasing team's position in real time during rain-affected matches. A common misreading is treating DLS targets as arbitrary; they are derived from historical data on how scoring rates decline as wickets fall, not an ad hoc adjustment.