Excel formula to extrapolate some numbers?

[RussA]

I need to create a formula, ideally in Excel that extrapolates out some CPU consumption figures based on hourly performance data going back 90/180/360 days etc. I cannot find anything that easily allows me to do this... please help if you can!

Thanks as always...

 

[oddjob62]

Put data into Excel, Plot data onto an X Y graph, Add a Trendline to the graph, set Forecast backwards or forwards however much you want, or you can display the equation of the trendline.

 

[Theguy]

Would that be using Y estimate= a+b*x?
Simple regression that is called btw.
a = intercept
b = slope.