@Backtotravel22 @MichaelSFuhrer The 20% includes all that. If you (implausibly) actually had people in good masks used correctly 100% of the time, it would be much more than 20% reduction.
@Backtotravel22@MichaelSFuhrer 20%包括所有这些。如果你（难以置信地）真的让戴着好面具的人100%的时间都正确使用，那将大大减少20%以上。