In writing a formula, how will you skip the cell with a missing value, i.e.,
#VALUE?
Example below.
A B C
D
1 Date opened Date closed # of days opened Area of
responsibility
2 1/13/2006 1/31/2006 18
Case Line
3 1/17/2006 2/14/2006 28
Light Line
4 1/22/2006 - #VALUE!
Case Line
5 2/10/2006 2/28/2006 18
Case Line

I want to find the total # of days opened for Case Line.
Note: Column C is the difference of C and B which is also written in a
formula =SUM(B2-B1), etc. thus giving the value of column C4 #VALUE since B5
is still open.