To get a handle on what 5 to 20% means in the context of Japan, I did some searching around. It turns out that the Tokyo Metro and BART have similar amount of t

To get a handle on what 5 to 20% means in the context of Japan, I did some searching around. It turns out that the Tokyo Metro and BART have similar amount of track (121.2 miles vs 131 miles), though the Tokyo Metro has many more stations. If the Tokyo Metro was operating at 5 to 20% or normal, it is still exceeding BART's daily ridership.