Problem:

Each row in columns A & B represents a shift worked during the first week of the year.
Column A identifies an employee, and column B lists the number of hours that employee worked on that shift.
Each employee may work any number of shifts per week, and they may be of variable length.
Columns C & D contain similar information for the second week of the year, and so on.
For any given employee and week number (cells A12:B14), we want to be able to calculate the number of overtime shifts (i.e. over 8 hours) that were worked.

Solution:

Use the SUMPRODUCT and OFFSET functions as shown in the following formula:
=SUMPRODUCT((OFFSET($A$3:$A$9,0,2*(B12-1))=A12)*(OFFSET
($B$3:$B$9,0,2*(B12-1))>8))