I imagine that figure is missed opportunity cost of other vessels that can't get through. There's a reason countries will fight wars over that canal. The alternative is to go around the entire continent of Africa.

I know blowing it up would be stupid and impractical, but I still think it would be fun to sneak a nuclear submarine thru there to "adjust" the situation a bit. Mainly because I just don't care the aftermath with the level of stupidity already going on in the world.