My Husband Has PSP And I Would Like A List

My husband has PSP and I would like a list of the stages and the symptoms that go with the stages. He almost has not speech, rides in a mobility chair, can't chew and swallowing is very, very slow. Dinner may take 3 hours to consume. He is loosing lots of weight and I am preparing heavy calorie foods. What stage is he in and what's up next?
Thank you, Emily W.