How to count yearly recurrence

Hello, I'm pretty new to Excel and English is not my first language, so I'm sorry if what I'm writing makes little sense. I need to count how many times a specific date (December 31st) recurs between a set date (in the past) and the day I open the file. Is there a way to do it? I tried searching online but I only found solutions that use searching between a list of typed out dates and that's not what I need (or how I can use it since my list would change constantly). Thank you all.