Writing Triggers

How can I put in a trigger that will fire every 8760 (number of hours in a year) time units? If there was a way to also allow the trigger to run its own loop that would be great. I have a model that wants to use two separate distributions for inter arrival time of items over the course of the year. The idea is that one distribution represents a distinct increase in flowitems but the increase visibly happens each year but follows no pattern over the course of multiple years (customers requesting our service). One distribution would be replaced for one month (730 hours) with another.

?

Make a user event in the tools menu. Make the first event time 8760 and check Repeat event. If you want it to happen at time 0, too, the simplest way is to make another nonrepeating event.