In this blog post ChartMogul CEO Nick Franklin wrote about a method of making trial-to-paid conversion rate metrics more useful using cohorts. The method involves measuring the % of trials that convert into paid subscribers within a defined number of days.  

One useful analysis is to compare your 30-day trial-to-paid conversion rate against your 90-day trial-to-paid conversion rate to see what % of trials are converting long after a typical SaaS free trial has expired.

It's possible to measure this in ChartMogul thanks to a filter attribute called "Trial-to-paid in days".

To use this:

1. Navigate to the Trial-to-paid conversion rate chart in your ChartMogul account
2.  Click Add filter and select "Trial-to-paid in days" from the attributes dropdown.
3. Choose the 'Less than' operator and define the number of days, e.g. '45'.
4. Click the button to Add the filter.  

This will give you your 45-day trial-to-paid conversion rate graph. You can then compare this against segments with longer or shorter "Trial-to-paid in days" values.