A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
COUNTIF() functions cannot use an OR() in its criteria but you could substitute with a simple SUMPRODUCT(). Try,
=SUMPRODUCT((B8:B500="NOB/PBL")+(B8:B500="OOB/PBL")+(B8:B500="OBL/PBL"))
... or,
=SUMPRODUCT(--(B8:B500={"NOB/PBL","OOB/PBL","OBL/PBL"}))