condition mean min max ZT0-3 5.4547175 4.370125 6.53931 ZT4-7 26.05 26.05 26.05 ZT8-11 50.13615 50.13615 50.13615 ZT12-15 0 0 0 ZT16-19 27.5586 27.5586 27.5586 ZT20-23 16.63475 16.63475 16.63475