Henry Baker:
I just heard on NPR from a Pakistani official that an area _the size of England_ is under water.
The number generally seen in news reports (instead of - or in addition to - the "one-fifth of the country") is 160000 km^2, which is about right (Pakistan = 803940 km^2; England = 130395 km^2). I have convinced myself that this much of Pakistan is in fact not "under water" but has been "affected by" flooding. Perhaps the former is a natural conclusion drawn on the latter in many people's minds but in my mind, "under water" implies pooled/standing water while "affected by" flooding might include areas that experienced torrential downpours with limited supra-surface water retention and/or areas affected because of sundry familial/economic connections to actual underwater regions. So I think my objection ends up being rather more linguistic than arithmetical.