When did 45 become Classic?

I understand some people's hair turns white, some turn grey, and some like mine turns loose. But I'm sitting in my garage and have the classic rock station on and they bust out with Motley Crue "Shout At The Devil".

I guess we could start hearing " Tom Sawyer" (without words of course) on an elevator??




Just a Friday morning thought....

When did 45 become Classic?