Time On Distance 
Corrected time is calculated as follows: Corrected time = Elapsed time – (ToD * Distance) With TimeonDistance (ToD) scoring, the
coefficient of time allowance of one boat will not change with wind
velocity, but will change with the length of the course. One boat
will always give to another the same handicap in s/NM, and it is
easy to calculate the difference in elapsed time between two boats
needed to determine a winner in corrected time. 

Where is it shown on the certificate? 



Time on Distance scoring
coefficients on simple scoring options on 

Coastal/Long Distance Time on Distance scoring coefficient also known as OSN (Offshore Single Number) is calculated as a weighted average of the predicted boat speeds in following conditions:  


Double handed coefficient is calculated with crew weight of 170 kg, while nonspinnaker rating is calculated for boat's performance without spinnaker. Double handed and Nonspinnaker ratings are given for both OSN and GPH calculations. 

Windward/Leeward Time on Distance scoring coefficient is calculated as the average of windward/leeward course (50  50 %) time allowances in three conditions multiplied by their respective weights:  
 25 % of Windward/Leeward at 8 knots  
 40 % of Windward/Leeward at 12 knots  
 35 % of Windward/Leeward at 16 knots  
A custommade ToD coefficient may be calculated using a different wind distribution matrix based on wind historical data or weather forecast for a particular race. Course model to be used shall be specified in the Notice of Race and Sailing Instructions. 
