I was re-watching Carlito's Way, which is set in 1975, the other night.

Carlito meets his old partner, Rolando, who is obviously well-off and surrounded by bodyguards. Carlito remarks that he looks like he's doing well for himself. Rolando replies, "Why not? Business is good." Carlito asks, "Smack?" Rolando replies, "The coca business, filete. That's all there is. Heroin is dead."

Is there any truth to this statement? Was Heroin "dead", at least in comparison to Cocaine, in the mid to late 1970s?

When did each drug peak and nadir arguably?