Creating rolling durational charts

Hi,

without going into too much detail, here is how the solution works in principle:

- use named ranges for your data series instead of absolute references.
- define the named ranges with the OFFSET function so they will adjust dynamically

With OFFSET you can define (and dynamically change)
- where a range starts
- how many rows it has
- how many columns it has

So for your scenario, your range will always have 12 columns, but you will need to determine on which month a range starts. This may be the last 12 months available or come from either user input or is calculated based on the current date, up to you.

Jon Peltier has some good articles on dynamic charts. Here is his tutorial on plotting the last 12 months in a chart.

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

hope that helps