RULE OF THE FLOATING SUBTRAHEND
rule of the floating subtrahend.The common-law doctrine that a plaintiff whose damage was
not caused entirely by the defendant must prove the amount of damage that is not attributable to
the defendant (the subtrahend) or else recover nothing. • The reasoning behind the rule is that
damage is an essential element of a tort claim, and the plaintiff has the burden of proof. If proved,
the subtrahend is subtracted from the total damage to determine the plaintiff’s recovery. [Blacks Law 8th]