Reports with recurring events DB Schema in SQL Server
Take a look at the way SQL Server handles this for SQL Agent job schedules. Specifically, read through the columns prefixed freq_* as these determine the frequency of execution.

You could use the same or similar table schema to store frequency information about your reports. You could even display 'next scheduled date' information quite easily if you also stored the creation date of the schedule for a particular report.

There is a good article on SQLServerCentral that dives into this and should help you develop a solution that would suit.