Tim Cook blamed iPhone market reduction on shrinking Chinese sales. Apple ordered its suppliers to cut down the number of new iPhone model units coming off their production lines right before Tim Cook published his letter to the Apple investors at the beginning of the month. Apple’s stock went on an accelerated drop, experiencing a severe 38% drop between a maximum valuation of 232.07 per share on October 3 to an all-time low of $142.08 per share the day after the investor letter. Apple also had to remove the iPhone 7 and the iPhone 8 out of German stores after Qualcomm posted $1.5B ( 1.34B) in security bonds to enforce a court decision.
Source: https://www.bleepingcomputer.com/news/apple/apple-orders-10-percent-production-cut-for-new-iphone-models/