That's enough to talk about Soma.
11% of children have ADHD 
We give them ritalin, which is meth.
Obviously not all of them, but quite a lot.
So 25% right there on anti-depressants, possibly ritalin.
This doesn't factor in all the other legal and illegal drugs.
The Soma prediction is not unreasonable at all.
Also, 'the rich' in America generally do have the burden of responsibility. Wall Street lawyer earning $800K is not an easy field trip.
I'm not trying to make an argument here, just pointing out some factual errors in case you wonder why you're being downvoted.
A very significant chunk of the population are taking drugs, legally or not legally, that materially affect our state of mind. This is a dystopian feature of 'A Brave New World'.