Is it bad if my EFC for fafsa dropped dramatically?

When I filed fafsa for the current school year (so last year) my EFC was around 1200. This year I filed and my EFC droped down to 45, which to me seems so drastic. The only true change is that I have a sibling who will start college next year but other than that everything is the same (except for corrections I made for my parents finances, because I made mistakes on previous fafsa without knowing- which still isnt a lot). What gives?