How far back in time when a single adult working 40 hours a week at minimum wage would pay 30% of there wages for rent? ?

Minimum wage isn't that HIGH, and shouldn't be.

If you only make minimum wage after a year, you are OVER PAID at that rate.

At least during the mid-1970's.  At that time I was paying about 30-percent of my salary for rent. 

Probably never. In the early 60s when minimum wage was $1 an hour, rents were around $100 so over half of a full time minimum wage pay.

Minimum wage was introduced in the USA in 1938.  The minimum wage was 25cents.

The minimum wage has never been viewed as a living wage and is not supposed to be.  If anyone is earning minimum wage and paying their own rent in the USA, they have always paid more than 30% of their income to rent.

That would depend on where in the world you live, what rental cost history is and wages earning history

It was in the 1970s.