The IRC certificate includes a DLR number (Displacement/Length Ratio) which is sometimes used to help determine class splits, for instance between racers and cruiser/racers. DLR is calculated as follows:

**DLR = (27.87 * IRC Displacement) / LWP^3** (Help with mathematical formulae)

Where:

a) LWP = LOA – BO – SO

b) IRC Displacement is directly related to the Boat Weight on the certificate. Therefore any change to Boat Weight will be reflected by a change in IRC Displacement.

c) The calculated value of DLR is rounded to the nearest integer value for printing on each boat’s certificate with 0.5 rounding upwards.

** *NOTE* IRC Displacement is an internally calculated figure and is NOT the Boat Weight on the certificate.**