Who has information about the Opium War?

On this issue, the academic circles generally adopt Marx's statement in the History of Foreign Relations of the Chinese Empire. In fact, Marx's statement has many mistakes. In my opinion, the total amount of opium imported into China before 1840 was about 400,000 boxes, worth about 220 million silver; Before 1840, the average annual outflow of silver in China was about 5-6 million. On the eve of the Opium War, the number of opium addicts in China was about 2.5 million every year.