How do you get percentage differences in Google Analytics between any two metrics?

Question

Say I wanted to make a conversation rate report (pretend a baked in report doesn't exist). How would I generate a report that shows me the percent of one metric compared to another? In that case, percent of sessions that with transaction compared to total sessions? I want to apply the concept to several different reports and different metrics. For instance I have a custom dimension for form errors. If I see a large number of form errors all the sudden if could just be a large number of users all the sudden. So I'd like to see a line graph of the percent of form error to users.

I am awful at asking questions so let me know if you need more info. Thanks for any help you can give!

Answer 1

Use Calculated Metrics. Specifically for this purpose. They are defined for every View in GA and you can have up to five in free version and a lot more in paid.

Another approach would be to use Data Studio to generate a report. there you could create a Calculated Field

Answer 2

In that case, percent of sessions that with transaction compared to total sessions?

Use segments. The first segment - all traffic, by default. And then create and apply segment (type Conditions) where Goal Compleсtion = 1.

So I'd like to see a line graph of the percent of form error to users.

In built-in line graphs you can compare metric with metric. A you sure that your "error form" is dimension? To compare metrics use custom report (type Explorer) contains 2 metrics you need to compare and at least 1 dimension.