Display only one category as a percentage/proportion of total

[david_tyrpak]

I have a Looker table with number of negatives and positives per month. I need my visualization to show only the positive rate (either as a percentage or proportion of total positives and negatives).

Looker can easily plot the percentages of both negatives and positives on the same graph, but if I "hide" negatives, the positive percentage balloons to 100%. Thats not right. I want to plot the actual positive percentage out of total. 

Is there a visualization option or table calculation I could use to achieve this?

Here's what my data currently looks like:

Status (pivoted)	Negatives	Positives
Month	Count Distinct Cases	Count Distinct Cases
month_1	3	7
month_2	4	2
month_3	1	5
month_4	5	5

Ideally my data would like this and I could plot the Positive Rate (as proportion or percentage):

Status (pivoted)	Negatives	Positives
Month	Count Distinct Cases	Count Distinct Cases	Positive Rate
month_1	3	7	0.7
month_2	4	2	0.33
month_3	1	5	0.83
month_4	5	5	0.5

[Shru · Accepted solution]

Maybe the pivot is giving trouble.

Try creating a filtered measure on the count distinct cases directly. Pass filter condition to identify positive cases from them. Then create another % measure from this new field (the option would be % of column). This will create a field to calc % of positive cases.

Now hide the previous measure column so that only month and exact % fields can be used to show in the Viz. 

[david_tyrpak]

So this worked ! (with a minor modification to the final step). In the final step I want percentage of row, not column. You need a table calculation to do that.

Here's the raw data:

Month	Count Total Cases
month_1	10
month_2	6
month_3	6
month_4	10

Then create filtered measure on Count Total Cases where I grab the positive cases. So the data then looks like this:

Month	Count Total Cases	Positive Cases
month_1	10	7
month_2	6	2
month_3	6	5
month_4	10	5

Then create a new table calculation where I calculate the proportion of Positive Cases out of Total Cases: ${positive_cases} / ${count_total_cases}}

That gives you this final format, where you can plot Positive Yield:

Month	Count Total Cases	Positive Cases	Positive Yield
month_1	10	7	0.70
month_2	6	2	0.33
month_3	6	5	0.83
month_4	10	5	0.5