Need to get difference between all values of column1 and column2?

[CapnShanty]

So I have two tables I've brought in from a database, each with the columns MetricName and MetricValue (they are for different months).

I need to have a table showing the % change between every single MetricName. I have tried many of the solutions on this forum for a problem similar to this, but they do not work as they all tell me "a single value cannot be determined" etc. 

I tried merging them in a query and then doing it, and I still get the same error. This does not change if I do a new measure, a new column, or a new quick measure; when it works, I get nothing but a single blank value. This can't be that hard...

[drewlewis15 · Accepted solution]

Assuming I am understanding the question correctly....

Join your two tables based on MetricName

Then create the following measure (replacing all references of tables and columns with your actual table and column names):

Difference =
VAR SumOfTable1 = SUM(Table1[MetricValue])
VAR SumOfTable2 = SUM(Table2[MetricValue])
RETURN SumOfTable1 - SumOfTable2

Below is the test data I setup to show this measure:

Table1:

Table2:

Join:

Measure:

Output: