Token for of Registrants/Form fills?

I have an alert sent to me when someone fills out a form (registering them for an upcoming event).  I need to keep an eye on how many people register, but this isn't my onlyl event so I can't necessarily keep count in my head of how many emails I've received.

Is there a way to insert a token to count the # of registrants?  Whether it's a flow step of +1 to some existing number, or a count of an existing smart list, or just # of times the form was submitted... any ideas out there?

Thanks!