condition mean min max ZT0-3 2.360825 2.34624 2.37541 ZT4-7 2.4424 2.4424 2.4424 ZT8-11 1.3947349999999998 1.3947349999999998 1.3947349999999998 ZT12-15 0 0 0 ZT16-19 1.460035 1.460035 1.460035 ZT20-23 2.129295 2.129295 2.129295