# 8.17.3.5 IfcQuantityCount

## 8.17.3.5.1 Semantic definition

IfcQuantityCount is a physical quantity that defines a derived count measure to provide an element's physical property. It is normally derived from the physical properties of the element under the specific measure rules given by a method of measurement.

## 8.17.3.5.5 Formal representation

ENTITY IfcQuantityCount
SUBTYPE OF (IfcPhysicalSimpleQuantity);
CountValue : IfcCountMeasure;
Formula : OPTIONAL IfcLabel;
WHERE
WR21 : CountValue >= 0;
END_ENTITY;