For the last year, the distances are adding on 1% every single run. so it shows 1.01 when i run one mile and 3.03 when I run 3 miles . Since the time is absolutely accurate, what happens is with the pace calculation being slightly wrong. That is an important factor when I am trying to run an accurate pace. When I bought the watch 3 years ago it was perfectly accurate, and really for the first two years, it is only the last year that this glitch has occurred. I have tried updating software, but no difference.