Unruly airline passengers worldwide by level of behavior 2018

The source defines:
Level 1: this category includes verbal aggression to crew members or other passengers, noncompliance with safety regulations, such as smoking in the lavatories, refusing to comply with the fasten seatbelt signs and standing during taxi in to retrieve personal items.
Level 2: this category includes acts of physical aggression.
Level 3: this category includes serious unruly behavior, which could be interpreted as a direct threat to the safety of a person or the aircraft. It also includes reports of self-harm.
Level 4: this category includes the most serious incidents where flight deck security could have been, or potentially was, compromised.