I thought I was something of a sign regulation expert. I'm a bit stumped with this, though.
Anyhow, many sign regulations use a formula like this to determine the maximum area of wall signs:
Maximum sign area = 1 x linear foot of wall where sign will be placed
Maximum sign area = 0.3 x linear meter of wall where sign will be placed
These have a rather inelegant solution for long walls, where 600 square feet of signage would be inappropriate on a 600' long wall; they'll have a fixed maximum.
I'm wondering if there are any wall sign area requirements that decrease the maximum sign area per linear wall foot gracefully. Not so much "1'2 x linear foot of wall where sign will be placed up to 200 feet, and then 0.5'2 for each additional linear foot to 400', and then 0.25'2 for each additional linear foot to 600", but something a bit simpler.