I need to get the count based on the criteria in two columns, In the below
example I am looking for a formula that will give me the count for defects
that are having the status of OPEN and of CRITICAL severity

Defect# Status Severity
1 Open Critical
2 Closed Showstopper
3 Open Important
4 Closed Critical
5 Open Minor
6 Open Critical
7 Closed Showstopper
8 Open Important
9 Closed Critical
10 Open Minor

Thanks in advance