As it says. I used to have that field and now I don't
"GPS Accuracy
The margin of error for your exact location. For example, your GPS location is accurate to within +/- 3.65 m (12 ft.)."
G
The accuracy number gave You false data, it had 2 option: #1: --- no signal/no lock , #2: 3m even with bad reception in house, so it was a totally useless info (the last device where it worked good was the Edge 1000...), the green gps lines in the upper left corner gives You the same "info".