From 1980 to 1985, cocaine use by high school seniors rose:
Assuming your chart is even correct, how quickly did you expect to see an effect for a policy change? Did you think they happened instantaneously? Doesn't it take some time for a crack down to start effecting behavior?
Your chart shows a decline right after 1980. I can argue that without the crack down, the *NORMAL* and usual increase in drug addiction would have kept rising, just as it did in China.
I can argue that it was Reagan's policies that caused a reversal of an upward trend.
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