From the New York Times: "In the 1990s, an estimated 3 to 5 percent of school-age American children were believed to have A.D.H.D., according to the Centers for Disease Control and Prevention; by 2013, that figure was 11 percent."
There's a stigma to these prescription drugs, so you co-workers will likely conceal the truth. And you won't be able to perceive they're on these substances.
Americans have a more competitive work environment than Europeans. They're raised to succeed, as the stakes are higher (less of a safety net, student debt, housing prices, etc...).
What's interesting, is that I suspect Adderall abuse is higher amongst those raised in upper middle class households. Adderall is common amongst my privileged friends, yet you would never know unless you were very close to them. In fact, they'll lie to others. The types from elite schools: Harvard, Stanford, Berkeley. The types in MD-PhD programs, FAANG companies, and "big law".
That is not addreal statistic, but adhd in kids statistic.
What % of children are admitted to Stanford? A sliver. What % of Stanford undergraduates make it to a "big law" firm? A small percentage.
The speculative point is that US men from UMC households who were admitted to elite schools and who subsequently went on to competitive jobs have higher Adderall abuse rates than you might expect. No, you can't find statistics on it. And to make the matter more difficult, they'll lie to your face about the subject.
This conjecture isn't even controversial, this notion is echoed throughout the broader culture. For example, see the following article from the New Yorker -- a magazine that caters to the families of these types: https://www.newyorker.com/magazine/2009/04/27/brain-gain . The article begins with the sentence, "A young man I’ll call Alex recently graduated from Harvard."
The US company I worked for encouraged vacation and offered almost the same amount as the European company I worked for (5 weeks).
Nobody was on Adderall in the US and the Europeans were putting in just as many late nights as the Americans.
I’d also argue that the Europeans often looked at the US politics as not “slightly left of center” but “fucking bonkers”.