Assistance with trend

I added a linear trend line graph in my analysis but I'm trying to prove a point and my big wigs are wanting to see some physical numbers. I'll add a sample of what I presented to them but they want to see what impact this linear decline will look like to our FY2013 budgets.

I added additional data on sheet 3. My hope is to trend out the trend of decline through the next fiscal year. I dunno, it might not even be possible within reliability.