Time tracking using git.coop issues
The only way I have found to tally time by month is to create a Milestone for a month and then add issues with time attached to it, this isn't ideal as we can't have issues spanning more than one month, perhaps there is a better way to do this, for March 2018 see:
https://git.coop/can/support/milestones/1
Note the time total in the right hand margin.