Three darts statistics from one leg

A strong start and a slow finish can belong to the same leg. This worksheet uses one invented 501, straight-start, double-out leg to calculate three-dart average, first-nine average and checkout percentage. Keep the dart counts beside the results: each statistic measures a different part of the leg.

By Dartboard Stats Editorial Team, dartboardstats.com. Written for CSWStats.

The fictional leg log

S means single, T means treble and D means double. A miss in this example scores zero. There are no busts. Each listed dart was actually thrown; the leg ends after the second dart of the final visit.

Check the scoring total: 140 + 100 + 60 + 100 + 69 + 32 = 501. Check the darts: 3 + 3 + 3 + 3 + 3 + 2 = 17. The final visit is two darts, not three.

Three-dart average

Multiply points scored by three, then divide by darts thrown: 501 × 3 ÷ 17 = 88.41 to two decimal places. All 17 darts count, including the two scoreless misses at double. Counting the unused third dart of the last visit would incorrectly give 83.50.

First-nine average

The first three visits score 140 + 100 + 60 = 300 points in nine darts. Their three-dart average is 300 × 3 ÷ 9 = 100.00. Here the gap between 100.00 and 88.41 describes this particular leg; it is not enough evidence by itself to diagnose a player's long-term weakness.

Checkout percentage

Use a dart-based definition: successful finishing darts divided by darts thrown with a chance to finish, multiplied by 100. Visit five has one such dart, the miss at D16. Visit six has two, another miss at D16 and the successful D16. That is one successful finish from three attempts: 1 ÷ 3 × 100 = 33.33%.

The T20 and S9 in visit five are setup darts, not darts that could themselves finish the leg from the score remaining. Do not count every dart in a checkout visit as a finishing attempt. A visit-based checkout measure uses a different denominator and must be labelled separately.

Change one thing and recalculate

Imagine the player hits D16 with the final dart of visit five. The leg now takes 15 darts. The three-dart average becomes 501 × 3 ÷ 15 = 100.20; the first-nine average remains 100.00; checkout percentage becomes 1 ÷ 1 × 100 = 100%. One changed dart produces a large percentage change because the checkout sample is tiny.

For a longer practice record, retain points scored, darts thrown, first-nine points and darts, and checkout successes and attempts. Combine the counts before calculating rates. A simple mean of displayed leg averages gives a short leg the same weight as a long one, which can distort the combined average.

Try it on your own log

Record the rules and the way your scorer handles busts, incomplete legs and finishing attempts before comparing sessions. This worksheet deliberately contains none of those ambiguous cases.