Okay, using Fatboy's formula - hopefully I finally did it right after a number of errors in my setup kept giving weird results - the steepest hill I think I've climbed covers three short blocks and the steepest part is 8.63. The average for all three is 7.07.

The distance is just 1065 feet. I've climbed it a few times with my old bike, which has a triple crank, but I have yet to make it with my newer bike (double crank). I've gotten half way up, but that's about it. I'm so slow, I have to worry about falling over so I can't make lock into the pedals - I'm afraind I'd start to fall and not be able to unclip successfully.