NPSP: How do you use "Close Date" with grants in progress?

Hello everyone. We use NPSP to track our grant applications and their stages from prospecting to closed won. 

I understand that the Close Date field is required. However, for grants that we are thinking about applying to, there really isn't a Close Date. For now I just use the last day of our current FY. 

May I ask how other folks use the Close Date field? Thank you!