Cricket has intrigued many people over the years, from Shahid Afridi's 'boys played well' to questionable distances of boundary lines to the 'adjustments' of pitches to suit a team's needs, all of them have been food for thought to say the least. But there's one system in cricket that just eludes any kind of understanding and perhaps is the most important system in the Champions Trophy.
Yes, we are talking about nothing other than the Duckworth-Lewis Stern system. The Duckworth-Lewis Stern or the DLS system is a system which is used to determine the winner or revise the scores of a cricket match should the match be interrupted that exact moment. DLS system was officially adopted by the ICC in 1999 when it was deemed that the old method of using run rate wasn't a proper determinant for deciding the match winner.
We at wittyfeed aim to enlighten you and give you the only guide you'll ever need to understand the DLS system.
Before the Duckworth-Lewis Stern method was invented, in the event the match was interrupted, the umpires used to determine the average run rate and decide the game winner. The previous method despite the flaws was used by the International Cricket Council (ICC) because there wasn't any better method to use. All of that changed when Frank Duckworth and Tony Lewis came up with Duckworth-Lewis system.
If Team A scored 250 runs without loss in 50 overs and Team B scored 195 runs for the loss of 5 wickets in 40 overs, according to the old method, the averages would've been used.
Team A 250 / 50 = 5 runs per over
Team B 195 / 40 = 4.875 runs per over
So should the match be halted at 40th over, Team A would've been the winner because Team B's average was lower than Team A. The old method didn't use the wickets remaining into calculation too.
Although the old method was easier to understand and comprehend, it didn't take into account the fall of wickets to determine the match winner. Perhaps the biggest flaw was - had Team B known that the match would've ended in 40 overs, they would've batted more aggressively which was never taken into account and that's why the old method was scrapped.
All of the problems were solved with the introduction of the Duckworth-Lewis Stern method named after two English statisticians Frank Duckworth and Tony Lewis who with the help of their professor Steven Stern devised what we know today as the Duckworth-Lewis Stern method.
So, how is the winning team calculated according to this method? Tighten your seat-belts!
According to the Duckworth-Lewis Stern method, a team has two resources to score:
1. Batsmen Remaining
2. Overs Remaining
Taking into account these two, ICC has devised a Duckworth-Lewis Stern table which is used to determine which team is in an advantageous position.
The DLS table takes into account the number of batsmen remaining and overs remaining to determine the percentage of scoring resources unused by a team.
Consider Team A while batting has put 200 runs for the loss of 5 wickets in 40 overs. This means they have 10 overs remaining and 5 batsmen remaining, a sneak peek into the DLS table shows us that they have 26.1 percent scoring resources unused.
As discussed in the previous example, Team A has 26.1 percent resources unused which means they used 73.9 percent of their available scoring resources.
So if 200 runs have accounted for only 73.9 percentage of runs, according to Duckworth-Lewis Stern method, the adjusted score for 50 overs would be:
200 x 100/73.9 = 270 Runs.
So in a match of 50 overs, team B would be asked to chase 270 runs instead of 250 had we used the old method.
Once again, let's take an example. Team A bats for 48 overs and puts 220 runs on board for the loss of 5 wickets. A sneak peek into the DLS table reveals that 6.8% of the batting resources were left unused. So team A scored 220 runs while utilizing 93.2% of their scoring potential.
220 = 93.2%
Score in 48 overs = 220/5
Revised score for 50 overs = 236 runs
Since Team A would've put 236 in 50 overs and since the match is reduced by 2 overs, according to DLS table, team B has 98.1 percent of their scoring resources available so the revised target would be 98.1 percent of the old target hence
236 x 98.1/100 = 231 runs in 48 overs.
The DLS table is determined by the International Cricket Council who keep in mind various intricacies and scenarios of the game that can happen and keep revising it every few years in order to keep it fair.
For the DLS to be implemented, the minimum overs for DLS to be used
ODI: 20 overs
T20: 5 overs
In case the minimum overs cannot be bowled, the match would be considered abandoned and no result will be declared.