A Combat results table or a CRT is used in wargaming to determine the outcome of a clash between individual units within a larger battle. The attacker and defender typically compare the relative strengths of the units involved in the clash and reduce these numbers to a ratio, which corresponds to a column on the table (for example 2:1 if the attacker is twice as strong as the defender). Less often, the columns may be based on the difference between the combatants' strengths, rather than the ratio (for example '3', if an attacker with strength 5 attacks a defender with strength 2).