Calculating # of Errors

[Amomin1988]

Hello, I'm new to Power BI and am trying to figure out how to do the following:

I have a table that shows # of readings present for every meter at a 900 second interval.  What I am trying to do is define the value of 0 as an error. I have meters with 0 readings and up to 3 readings within an interval.  

#Error = |Max Readings - Actual| 

Total Possible = Total Errors + Total Actual

What I'm trying to do is create a line graph that will show errors/gaps as spikes.  I've tried to create if then statements but I can't seem to get what I need.  Would this be a Measure or a Custom Column?

Edit: Created a calculated column with if/then/else statements labeling a specific values are error and non-error.  

[Anonymous]

This 

#Error = |Max Readings - Actual| 

Total Possible = Total Errors + Total Actual

can be simplified to

#Error = Max Readings - Actual // since Max Readings (=3) will always be at least as big as Actual, right?

Total Possible = Total Errors + Total Actual = Max Readings = 3

A file is attached with something inside you could experiment with.

Best

Darek