DLS Method Explained: How Duckworth-Lewis-Stern Sets Revised Targets
A step-by-step explanation of the DLS method — how it works, why it replaced previous rain-rule systems, common DLS scenarios, and why people find it confusing.
The DLS (Duckworth-Lewis-Stern) method is cricket's official mathematical system for recalculating targets in rain-affected limited-overs matches. Most fans find it confusing, but its core logic is surprisingly intuitive: it measures how many 'scoring resources' each team still has available, and adjusts targets proportionally.
The Core Concept: Resources
DLS assigns every batting team a 'resource percentage' based on two factors: overs remaining and wickets in hand. A team starting their innings has 100% resources. As overs pass and wickets fall, resources decrease. The key insight is that resources are non-linear: the last 10 overs with 8 wickets remaining are more valuable (can score more) than the last 10 overs with 1 wicket remaining. DLS captures this asymmetry — simple proportional adjustment (pro-rata) does not.
How DLS Sets a Revised Target
In the most common scenario (Team 2's innings interrupted): (1) Calculate what percentage of resources Team 1 used batting first (usually ~100% for a full innings). (2) Calculate what percentage of resources Team 2 will have after the interruption (reduced overs or lost overs within innings). (3) If Team 2 has fewer resources than Team 1, scale down the target proportionally. If Team 2 somehow has more resources, the target is increased.
Example: Team 2 Has Fewer Resources
Team 1 scores 280/6 in 50 overs (using 100% resources). Rain reduces Team 2's innings to 40 overs. At the start of their innings, Team 2 has approximately 86.4% of resources available (100 overs remaining → 40 overs, no wickets lost). DLS target = 280 × (86.4/100) = 241.9 → revised target: 242 runs in 40 overs. This means Team 2 needs 242 to win, not the 'proportional' 224 that simple pro-rata would give.
Why DLS Is Better Than Previous Systems
Before DLS, the 'highest scoring overs' method was used. It replaced the 50 lowest-scoring overs of Team 1 with overs not played by Team 2. This method failed spectacularly in the 1992 World Cup semi-final when South Africa, needing 22 from 13 balls, had their target recalculated after rain to 21 from 1 ball — mathematically impossible. DLS eliminated this by considering resources in a more sophisticated way.
Common DLS Confusion: The Score at Interruption
DLS is most confusing when Team 2's innings is interrupted mid-over. If Team 2 is 80/2 after 20 overs when rain stops play for the day and only 30 more overs are possible, the DLS par score changes because Team 2's resource percentage is now calculated from their actual position (80 runs, 8 wickets, 30 overs remaining) rather than from the start of their innings. Teams trailing DLS target mid-innings can see their required total change dramatically when more rain falls.
Frequently asked questions
What does DLS stand for in cricket?
DLS stands for Duckworth-Lewis-Stern — named after statisticians Frank Duckworth, Tony Lewis (who created it), and Steve Stern (who updated the formula). It is the ICC's official method for setting revised targets in rain-affected limited-overs matches.
Why is DLS fairer than simple pro-rata?
Simple pro-rata would just scale the target by overs remaining (e.g., 40/50 × 280 = 224). But a team batting 40 overs with 10 wickets has more scoring resources than a team batting 40 overs mid-innings with 3 wickets down. DLS accounts for wickets remaining, which pro-rata ignores.
Can DLS increase a team's target?
Yes. If Team 2's innings is interrupted when they have more resources remaining than Team 1 had at that stage, DLS can increase the target beyond Team 1's score. This is rare but occurs when Team 2 is cruising ahead of the required rate when rain falls.