I can find out how many critical bugs have been opened in the last month using a JQL query like
issuetype = Bug
AND priority = Critical
AND status in (Open, "In Progress", Reopened)
AND created >= 2012-02-13
If I want to compare this figure, with the corresponding figure from last year, a naiive attempt at getting last year's equivalent might be
issuetype = Bug
AND priority = Critical
AND status in (Open, "In Progress", Reopened)
AND created >= 2011-02-13
AND created < 2011-03-13
But of course this is completely wrong, because it will tell me how many critical bugs that were created between 2011-02-13 and 2011-03-13 currently have staus open, in progress, or reopened. What I want to know is how many of these bugs had such a status one year ago.
I don't know if the JIRA data model, allows such a query to be formulated, but if it does, I'd appreciate it if someone could show me how.