Duckworth-Lewis-Stern (DLS) Method Explained
What is the DLS method in cricket, how does it work in rain-interrupted matches, and why was it created? Plain-English guide with worked examples.
The Duckworth-Lewis-Stern (DLS) method is the mathematical formula used to calculate revised targets in limited-overs cricket matches interrupted by rain or other disruptions. It replaced simpler but flawed methods from 1997 onwards and is now the official ICC standard for all interrupted ODI and T20 matches.
Why DLS Was Needed
The most famous example of pre-DLS failure: at the 1992 World Cup semi-final, South Africa needed 22 runs off 13 balls to beat England — rain reduced them to needing 22 off 1 ball. The prior method (counting down the lowest-scoring overs) produced this absurd result. DLS accounts for both runs remaining and wickets remaining simultaneously.
The Core Concept: Resources
DLS is based on 'resources' — each team has 100% resources at the start of their innings. Resources are consumed by overs used and wickets lost. A team with 10 overs and 5 wickets has more resource than one with 10 overs and 1 wicket. DLS calculates how much resource each team has used when interruptions occur and sets revised targets accordingly.
Minimum Overs for a DLS Result
| Format | Minimum Overs (Chasing Team) |
|---|---|
| ODI (50 overs) | 20 overs |
| T20I (20 overs) | 5 overs |
| T20 domestic | Varies by competition rules |
Frequently asked questions
Who are Duckworth, Lewis, and Stern?
Frank Duckworth and Tony Lewis were English statisticians who developed the original D/L method, first used in 1997. Steven Stern, an Australian statistician, became the official custodian of the method in 2014, leading to the Stern addition. Duckworth passed away in 2022.
Why does DLS sometimes produce targets that seem unfair?
DLS works on averages across all cricket and does not adjust for specific match context or batting strength. In extraordinary circumstances — very high first-innings scores or severely disrupted play — targets can appear counterintuitive. However, across thousands of matches, DLS is demonstrably fairer than any simpler alternative.