The ComDev project also maintains the Board Reporting Wizard tool, that collects some statistics about your project, and allows a PMC chair (or other member helping out) to draft a quarterly board report. The Wizard also has some simple formatting checks, and can also post your report directly to the board agenda - no other steps needed!
Try out the Board Report Wizard here: (ASF login required, you will only see projects you have access to)
https://reporter.apache.org/wizard/