DAYS FROM( DATE OF( 1, 1, YEAR OF( DateVar ) ), DateVar ) + 1
HotDocs does not provide a DAY OF YEAR() model. This computation provides that functionality. For a given DateVar, the computation determines the day of the year from 1-365 (366 for leap year). For example: New Year's Day is day 1, Valentine's Day is day 45, etc.
The day of year is found by determining the DAYS FROM January 1 of the year in question to the given DateVar (you could also use TODAY). We then add one day (otherwise Jan. 1 would be day zero). The resulting day of year is returned as a number value.
This template has everything you need set up and configured for you. It will work as-is, or can be adapted to your variable and dialog names. It contains: 1) sample Word and WordPerfect templates (or an Automator form) to demonstrate an implementation of the computation, 2) a component file containing the computation and all supporting dialogs and variables, and 3) instructions for adapting the computation for your use.