How far is it?

Below is Garmin GPS Data I gatherer last summer.   Each number represents 6 laps of my backyard trail ...

4.38
4.4
4.41
4.46
4.47
4.51
4.51
4.53
4.56
4.56
4.57
4.6
4.6
4.62
4.62
4.65
4.66
4.66
4.66
4.68
4.68
4.69
4.69
4.69
4.7
4.71
4.71
4.72
4.72
4.73
4.73
4.74
4.74
4.74
4.75
4.76
4.77
4.77
4.78
4.78
4.78
4.79
4.79
4.79
4.79
4.79
4.79
4.8
4.8
4.8
4.81
4.81
4.82
4.82
4.83
4.84
4.85
4.85
4.86
4.87
4.88
4.89
4.89
4.9
4.91
4.91
4.92
4.93
4.93
4.95
4.95
4.95
4.95
4.97
4.98
5.01
5.01
5.02
5.03
5.03
5.06
5.06
5.09
5.09
5.28

Now remove the top and bottom 10 results ....

4.57
4.6
4.6
4.62
4.62
4.65
4.66
4.66
4.66
4.68
4.68
4.69
4.69
4.69
4.7
4.71
4.71
4.72
4.72
4.73
4.73
4.74
4.74
4.74
4.75
4.76
4.77
4.77
4.78
4.78
4.78
4.79
4.79
4.79
4.79
4.79
4.79
4.8
4.8
4.8
4.81
4.81
4.82
4.82
4.83
4.84
4.85
4.85
4.86
4.87
4.88
4.89
4.89
4.9
4.91
4.91
4.92
4.93
4.93
4.95
4.95
4.95
4.95
4.97

That leaves 65 results and when averaged it works out to 4.78.   

So as I have always though 6 laps of the backyard trail is 4.8 Ks.   

Now remove the top and bottom 10 results again ....

4.68
4.69
4.69
4.69
4.7
4.71
4.71
4.72
4.72
4.73
4.73
4.74
4.74
4.74
4.75
4.76
4.77
4.77
4.78
4.78
4.78
4.79
4.79
4.79
4.79
4.79
4.79
4.8
4.8
4.8
4.81
4.81
4.82
4.82
4.83
4.84
4.85
4.85
4.86
4.87
4.88
4.89
4.89
4.78
4.78

and the average is .... 4.78!