condition mean min max ZT0-3 2.6420458333333334 2.2543466666666667 3.029745 ZT4-7 1.6745299999999999 1.6745299999999999 1.6745299999999999 ZT8-11 2.3311 2.3311 2.3311 ZT12-15 2.66576125 2.5617825 2.76974 ZT16-19 2.34289 2.04972 2.63606 ZT20-23 0 0 0