condition mean min max ZT0-3 17.736416666666667 11.68995 21.9685 ZT4-7 6.21518 6.21518 6.21518 ZT8-11 5.850225 5.850225 5.850225 ZT12-15 12.38997 10.04219 14.73775 ZT16-19 22.1386 22.1386 22.1386 ZT20-23 25.68155 25.68155 25.68155