Hi Janice

When you select row 7 and insert a new row, what you are doing is
moving all the cells below, i.e you are moving your range $A$7:$Z$50
too.

Now coming to your problem. Do this : keep your row 7 blank and have
data from row 8 to 51( your vlookup array should be($A$7:$Z51) . Next
time you want to add a new month, select row 8 instead of 7 and inset a
new row. And you have what you wanted. The new range in your formula
has changed from $A$7:$Z51 to $A$7:$Z52.

What we have just done is insearted a row which is within the range of
rows 7 to 51 and therby our range automatically expands.

Thanks
Karthik Bhat
Bangalore