Cow No.  PCV  s_{i}^{2}  Mean  CV  CV^{2} 
1.  2. 
1  33  35  2  34  0.042  .002 
2  26  23  4.5  24.5  0.087  .007 
3  29  29  0  29  0  .000 
4  32  35  4.5  33.5  .063  .004 
5  31  28  4.5  29.5  .072  .005 
6  31  31  0  31  0  .000 
7  31  34  4.5  32.5  .065  .004 
8  31  29  2  30  .047  .002 
9  35  33  2  34  .042  .002 
10  21  24  4.5  22.5  .094  .009 
Mean 
  2.85  30.05   .00355

Let's return to the example of two repeated measurements of packed cell volume that we used to demonstrate calculation of the withinsubject standard deviation.
By using the root mean square approach:
Withinsubject coefficient of variation = (√0.00355) × 100 = 5.96%
By dividing the within assay standard deviation
by the overall mean:
Withinsubject coefficient of variation = ((√2.85) / 30.05) × 100 = 5.62%
The betweensubject coefficient of variation is obtained from the variance of the means of the duplicate observations.
Hence betweensubject coefficient of variation =
√(2 × 15.47) / 30.05 = 18.5%