Using Excel 2000

Column A contains user names
Column B contains their department
Column C thru X contains number of years in certain field

I would like to return a sum at the bottom of the list for each field
column. I want a sum of years experience for each department

Thanks in advance

Example:

Col A        Col B     Col C
Name         Dept.     Years
John Doe      1           4
Jane Doe      1           2
Jake Doe      2           8
Lou Doe       1           1
Jim Doe        2           10
Paul Doe      3            20
Dan Doe      4            14
Ray Doe      3             12

At bottom of my sheet:
Department         Total Years
       1                        7
       2                        18
       3                        32
       4                        14