condition mean min max ZT0-3 0.7302016666666666 0.6861845 0.790656 ZT4-7 0.222082 0.222082 0.222082 ZT8-11 0.5423215 0.5423215 0.5423215 ZT12-15 1.3675374999999999 1.2532649999999999 1.4818099999999998 ZT16-19 1.38437 1.38437 1.38437 ZT20-23 1.63857 1.63857 1.63857