Each side's basic combat result is equal to the number of unsaved wounds it caused during this Combat phase, plus any unsaved wounds a unit caused by shooting if it chose to Stand & Shoot as a charge reaction during this turn. In other words, each Wound the enemy side lost this turn due to a Stand & Shoot charge reaction or during the Combat phase is counted and is worth 1 combat result point.
Should an attack or rule cause an enemy model to be removed from play as a casualty, it counts as having lost a number of Wounds equal to the number it had remaining at the time it was removed.
Note that it is important to count the number of Wounds lost, rather than the number of casualties, because many models have more than one wound.