This is an incorrect way to look at the available data. Would you say that the "War on Murder" wasn't working because we still have murders?
It is irrational to believe that with our current approach that we can reduce the rate of addiction (which has been at ~2% for over 100 years.) What the current efforts do is to STOP AN INCREASE.
The NORMAL trend of drug addiction in any society is a constant increase. This is not a theory, we have an actual example that proves this.
And a more in depth chart.
What you are seeing in both these charts is something called a "Logistical growth curve." It is applicable to the spread of disease, or in this case, drug addiction, based on the availability of supply and the exponentially increasing numbers of social contacts.
The NORM is that drug usage will continuously increase. To hold it flat (No increase in 100 years) requires considerable effort, and it is proof of the success of the effort to suppress it.
Misery increases drug abuse. A miserable people will seek out greater escapes.
We are not holding steady because of the WOD. We are holding steady because we are a (semi) free and secure people.
The lovely rat experiment that proved that everything is horribly addictive? Yeah. Somebody redid that experiment, but this time they put the rats in a nice cage with toys, company and stimulation. The rats did try the drugged water, but ended up rejecting it the majority of the time, with the occasional sip and nothing more.
The rats that drugged themselves to death in the early experiment were in miserable conditions and reached for drugs as their only means of dulling the boredom and pain.
China has never been known as a ‘paradise’ by any definition. Miserable Chinese people turned to drugs. Shocker. And people in hospitals use more narcotics than any other population. Another surprise. /s
As you've said, "Till someone presents an argument that there are better figures, I will have no choice but to use what is available."
What's available says that addiction was low and declining in post-Civil War America: "In 1880 [...] there were over 400,000 opium addicts in the U.S. [...] By 1900, about one American in 200 was either a cocaine or opium addict." (http://web.archive.org/web/20110529221013/http://www.justice.gov/dea/demand/speakout/06so.htm) 400,000 in a population of 50M is one in 125 - ergo, between 1880 and 1900 addiction declined.