my clock run 1.25 seconds per day fast accord to my measurement . not bad , but I like to know what time it \* really \* be ... so after a month , I be -rrb- 30 seconds ahead of time - over a minute fast in two month . it might not bother you , but I run a lot of conference call in my work , and need to start\/stop right on the top -lrb- or half -rrb- of the hour . I would be satisfy with + \/ - 1 second per month ... but more than that every day ? Time for I to find another , more accurate clock .