Ping has increased to 45-50 from 19-20 randomly

I am connected via ethernet and have 1000 download and 250 upload. My ping has been 19-20 for 4 years and now has jumped and wont go back to normal. I have upgraded my modem and tried multiple ethernet cords, I have seen other with this problem but does anyone know why this is happening or how to fix? The game is much les fun to play when your ping is double what you are used to for years...