An alternative approach:

http://peltiertech.com/Excel/Charts/DynamicLast12.html

- Jon
-------
Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
http://PeltierTech.com
_______


"Damon Longworth" wrote in message
...
Set up a table using the offset function to retrieve the last 13 rows from
your data table. Use this new 13 range table as the source for the chart.
Copy a formula similar to this down 13 rows:

=OFFSET($A$1,COUNTA(A:A)-ROW(A1)+1,0)

--

Damon Longworth

2007 East Coast Excel / Access User Conference
April 18-20, 2007 - Providing Microsoft Excel training and Microsoft
Excel
Classes
Atlantic City, New Jersey
www.ExcelUserConference.com/ECEUC.html

"Box666" wrote in message
oups.com...
I have a chart based on a worsheet that contains data on a monthly
basis for the last 2 years.

I only want the chart to show data for the last 13 months, I want it
to automatically update each month after i have added another row
(month) of data to the worksheet.

is this possible.

Bob