New to reports, what am I missing?  I want to produce a simple report of the daily count and the running average.

Date                  Users

04/17/2016            0

04/18/2016            39

04/19/2016            39

04/20/2016            36

04/21/2016            41

04/22/2016            34

04/23/2016            0

My thought was to use an aggregate formula in a Chart view but that is not with success.

The desired result for the chart would be.

X-Axis Date

Y-Axis Unique Users

Y-Axis Average users running 

My concept was to count all dates with the ability to remove the weekends so as to get a better working average.

first date count would = 1 divided by Users = 0 with a result of #Div/0!

second date count would = 2 divided by users = 39 with a result of (0+39)/2 = 19.5

third date count would = 3 divided by users = 39 with a result of (0+39+39)/3 = 26

4th date count would = 4 divided by users = 36 with a result of (0+39+39+36)/4 = 28.5

Not only cant I get that to work, I cant even figure out how to eliminate weekends.

Any help would be appreciated. 
Thanks

-g-