| N | Min | Max | Range | Mean | Var | Std | CV(%) |
251-10 | 50 | 16.7 | 23.24 | 6.54 | 19.82789 | 1.563093 | 1.250237 | 6.305447 |
251-12 | 50 | 15.48 | 25.41 | 9.93 | 19.33091 | 5.158352 | 2.271201 | 11.74906 |
251-14 | 50 | 5.84 | 26.7 | 20.86 | 19.865 | 9.817665 | 3.133315 | 15.77304 |
251-16 | 50 | 15.55 | 33.35 | 17.8 | 20.53787 | 8.321517 | 2.884704 | 14.04578 |
251-18 | 50 | 14.69 | 22.96 | 8.27 | 19.06429 | 2.506779 | 1.583281 | 8.305083 |