I am trying to create a report that shows the changes of a calculated text field over time. For example, when a JIRA issue is created in March, this custom field is "Not calculated". Then, this field is changed to a value of "Low" in April. I need my report to show that the value of this field at the end of a monthly time period, so March would displays this issue as "Not Calculated", and it April it would show it as "Low". I have attached screenshots of custom field and what our report currently looks like. Any help will be appreciated.

