I think this should be fixed. Clearly the numerals are signed (good example here: https://www.mapillary.com/app/user/ikeda6983?lat=43.099950000000035&lng=-89.349241&z=19.9&pKey=760783971131307&focus=photo&x=0.4087984809260903&y=0.5509205180925127&zoom=1.6848837209302334 ) and they're used in the city's property records. The source of the numeric names all seems to come from the TIGER import.