This would have to be one of my biggest issues with Jira. being able to go back 12 months is not helpful when you are trying to compare year on year issue growth.
Trying to justify extra staff without being able to go "Well in 2016 we averaged 30 tickets raised a month, 2017 we averaged 90 tickets raised a month, 2018 we averaged 150 tickets a month, and so far in 2019 we've averaged over 400 tickets a month." to show the growth of your helpdesk. This functionality was available in our previous helpdesk software before upper management forced a migration over to Jira service desk because they were already using Jira for project management and had this idea that one system would be superior. Even though we've lost 80% of the functionality our old system had and the only recourse we have is to go on Atlassians forum, find a bunch of other system administrators complaining about the same issue, and vote on a Jira ticket that maybe one day will lead to the functionality that you think would be standard.
And in the meantime deal with the current threadbare system for five years.
We recommend companies to use JSM, but they can get a maximum of one year annual report in reporting. I think it's funny, it's pretty hard to explain that to my clients because it doesn't make sense.