Excel 2007 : Calculating Active Employees with Hire and Termination Dates

Hi!

This may be tricky however if someone could get this to work it would be a great help.

My goal here is to determine the number of active employees (non-terminated) on a weekly basis starting 9-May-2011 to present. I am looking for a data point for each week so I can graph the number of active employees over time.

The information I have provided is the employee ID, and the corresponding hire dates and termination dates for that employee. What makes this tricky is that some employees have been hired/laid off multiple times.

Is this possible? I beleive I have enough information here to make this work but I cant seem to figure out how to go about it. Please let me know if you have any questions.

Thanks!