Predict if two lines intersect and when?

[ExcelLLAA]

Hello,

I am working a new job that requires a lot of Excel use. So far, this site has been incredibly helpful. I'm graphing revenue over time from 2012 and 2013 and I want to know if and when the lines will intersect. The x-axis is dates (e.g. July 1-10) and the y-axis has total revenue (e.g. $30,000). Right now, the 2013 revenue is significantly lower than 2012, but I want to know if they will intersect (and when) if the 2013 data continues to grow at its current rate.

Please help! Thanks!

 

[farmerscott]

Hi,

Sorry I am no expert in this area...........but will try.

What chart/line function/s are you using to extrapolate your data? LINEST, TREND, GROWTH?

To do it mathematically, where the two lines join they will have the same y value. Hence equation of line 1 equals the equation of line 2. All you have to do is solve for x.

(Does Excel give you mathematical equations of lines??)

FarmerScott

 

[ExcelLLAA]

I don't really know how I extrapolated the data. I just highlighted the cells and then clicked "graph" and selected a line graph. I am now wondering if the lines will ever intersect because the 2013 line is growing at a slower rate than 2012 and it is also starting significantly lower than 2012. (I am no expert in this area either, nor am I close to an expert in math.)

Thanks for your help and I will continue to google search and do some trial and error stuff. At this point, I am most interested to see if they will ever intersect and other information is not as important.