Excel 2003 - hope this is the right group to ask.

I am trying to find a formula for a time sheet for employees. I will try to
show an example:

Col A (job number) Col B hours in day
2103x 4.0
2402 2.0
1234 2.0
___
sub-total 8.0

This continues in four blocks for each working day of the month. At the end
of block 4, I need a total of all the sub-totals. The person who set up the
sheet just had:
=SUM(C14+C23+C32+C41+C50+C59+C67+C75+G14+G23+ G32+G41+G50+ G59+G67+G75+
K14+K23+K32+K41+K50+K59+K67+K75+ O14+O23+O32+O41+O50+O59+O67 etc, but I'm
sure there must be an easier way!!

I would really appreciate some advice - I have tried using Help but don't
really know how to phrase the question!

TIA