# Add average line to scatter graph in Google Spreadsheet

I have the following scatter plot in Google Spreadsheet, and I would like to add a line that averages all my points.

Can I do that? And if yes how?

-
Have you seen my answer? Does it answer your question? If no, can please give me some feedback on how to answer your question more properly? – Jacob Jan Tuinstra Dec 11 '12 at 21:00

First, calculate the linear regression factors: y=ax+b with the following formula:

``````=LINEST(B2:B21;A2:A21)
``````

Then add another column next to the y-axis and name it calculated y-axis. Build the following formula to calc. the y-axis and copy that for all x-values.:

``````=\$D\$3*A2+\$E\$3
``````

Next is a piece of cake. Add the calculated y-axis to the existing data range or add it seperately.

UPDATE: I've added the calculated mean value as well, in order to be absolutely sure to have answered your question properly, see plot:

See example file for more details: plot regression example

-