GitClear has dedicated itself to the pursuit of proving the empirical value of Diff Delta as it relates to Story Points, an estimation of "Software Effort."
GitClear is designed to detect your Story Point column without any intervention from the user. If the column you use is named "Story Points" or contains the word "Points" and multiple tickets with numeric values, then the Story Points field will be automatically detected with no intervention from you.
If you use a non-standard field name for your Story Points, you can configure GitClear to associate this column with your "Story Points" label. To do this, once you've connect to your issue tracker, you can visit Settings -> Issue Tracker Projects, and then choose a new value in the "Story Points" field:
Choosing the Story Points field for a Jira connection
Once you click the checkbox, you can enter the column name where your Story Points are stored.
To see how well Story Points correlate with Diff Delta in your resource(s), visit Issues -> Stats (the default tab) at which point you can see your Story Point correlation among the graph boxes:
Viewing Issue Stats and Diff Delta correlation
Below the main graph for Diff Delta by issue, you can see stats for the number of Story Points completed by day, week, month, or year:
Showing the total number of Story Points associated with Jira issues marked "Resolved" in 2018
This can be a useful way to calibrate your instincts for what's getting done with what the data says.