I'm betting mid to late 80's. The downtube bosses mean it wouldn't be a lot newer than that, and the graphics look newer than the 70's.
Looks like a decent, mid range frame. The simple lug work makes me think its not a higher end frame.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.