condition mean min max ZT0-3 4.22328600275 3.7571983515 4.689373654 ZT4-7 5.4594633882500005 4.0213143055 6.897612471 ZT8-11 8.978054382749999 8.017621692 9.9384870735 ZT12-15 11.6880479045 9.322117157000001 14.053978652 ZT16-19 9.696517687250001 7.917281852 11.4757535225 ZT20-23 17.210086265 15.82856538 18.59160715