Dear All,
I am sorry that I could not find any better subject for this post. I
need a solution for the following counting. I have (identification)
numbers (each number can occur frequently) in column B and dates for
the ID numbers in column G. I would indicate in column L if months in
the dates are continously exist for the numbers. If there is a gap
between 2 month in the column (like G5=11/Jun/2011 and G6=05/Aug/2011)
I need an indication for example "There is a GAP".

Well I am not sure if I was clear, here is a part of my table.

B5=460050001 G5=11/Jun/2011
B6=460050001 G6=12/Jul/2011
B7=460050001 G7=10/Aug/2011
B8=460010003 G8=05/Dec/2010
B9=460010003 G9=01/Jan/2011
B10=460010003 G10=05/Mar/2011
B11=460010003 G11=06/May/2011
etc.

In this example there is a gap for ID 460010003 at row #10, so L10
should indicate "GAP". My problem is how to automate this if I do not
know which is the last row. The 1st row is #5. There is no any blank
cells from row #5.

Thank you for anyone's help in advance.
Tamas