Can a club change Portsmouth Numbers?

Yes. The national list is a starting point. When your own results consistently show a class finishing ahead or behind on corrected time, adjusting the number is the right call.

Does PY Online suggest club-specific numbers?

Yes, if you submit PY returns. The portal analyses your results and suggests a PN for each class at your club, along with a confidence level based on how many races you have submitted.

How do I set a number for a class that has no national PN?

Start from a similar boat of comparable speed, collect elapsed times for both on the same course, and apply the provisional PY formula to get a starting number. Treat it as a trial and review after a season.

Club adjustments and setting your own handicaps

Portsmouth Numbers are a national average. Your club's course, tidal conditions, and typical wind range may mean some classes consistently outperform or underperform what the national figure predicts. When that pattern repeats across a full season, adjusting the number is the right call.

Where to start: the PY Online portal

If your club submits PY returns, you do not need to guess. The PY Online portal analyses your submitted results and suggests a club-specific PN for each class, along with a confidence level. A high-confidence suggestion is based on a large enough sample from your club alone; a low-confidence one means the portal is working from fewer races and should be treated as a starting point rather than a firm recommendation.

Clubs typically adjust in small steps (5 to 10 PN points at a time), then run another season before reviewing again. Larger jumps are rarely justified and harder to explain to competitors.

Setting a number for a genuinely new class

If the class has no national number and no local history yet, start from a similar boat of comparable speed. Once you have representative elapsed times for both the new class and the benchmark boat on the same course, use this formula to get a provisional PN:

Provisional PY = (New Boat Elapsed Time / Benchmark Boat Elapsed Time) x Benchmark Boat PY

For example, if the new boat takes 52 minutes and the benchmark (PN 1100) takes 48 minutes: Provisional PY = (52 / 48) x 1100 = 1191.

Treat the result as a trial number for at least a season and review it against your own results before fixing it.

Keeping it honest

National numbers pool results from many clubs, which is why they carry more weight than any single club's data. Every local adjustment trades some of that reliability for a better local fit. Adjust when your results make a clear case for it, document the adjusted numbers in your sailing instructions, and check them against the latest national list each year.

Sailboat Racing lets you create and apply your own club handicap lists alongside the national ones. Set up your club.

Last updated: 2026-06-03