Probably eyeball it cuz I'm lazy, but I never had a dealer or did hard drugs other than alcohol.
Spend a year in a remote Russian village or a tribe in the Amazon somewhere? You're guaranteed to be safe, although maybe not comfortable at all times.
I'll go remote Russian village. The drugs in the Amazon would probably be too intense for me. some nice Russian vodka will warm me up and make the year go by quick.
go back to when you were a child or go back ten years?