Do you have a link for that. My Mathematician friend would love it, he writes Pain articles, he has EDS a rare painful disease. He debunks the CDC all the time. https://www.painnewsnetwork.org/stories/2018/3/10/what-the-krebs-opioid-study-didnt-find
Sure, but not a very good one. It doesn't say where this study came from.
https://www.studyblue.com/notes/note/n/miderm-flashcards/deck/712694
Wikipedia has an entry with a similar chart.
https://en.wikipedia.org/wiki/History_of_opium_in_China
I've never seen a chart that shows the Opium trade after 1880, and I think this is because by this time it had become quite embarrassing to the British, and so they may have stopped releasing the figures on what they were doing.
Opium continued to be imported into China up until the 1940s, and then dictator Mao came along and executed anyone caught engaging in the trade or usage of Opium.