Can't see the 'created date' in the 'statistic type' dropdown on the issue statictics gadget

The issue-statistics gadget requires fields that have lists of possible options. Lists of users, select lists, radio-buttons, components - all of these are lists of options.

But strings, numbers and dates are not - they have effectively infinite unbounded options, and hence, are not suitable for the gadget. You could, in theory, code around this (generate a list on-the-fly and use that instead of reading the field list), but you'd still have the potential for unbounded results which would then fall over.

As an example, imagine the main Jira I look after at the moment. 420,000 issues. Someone does the coding above, so that the gadget can use "created date/time". That's a list of around 420,000 date/time values...