condition mean min max ZT0-3 21.13815 20.03855 22.23775 ZT4-7 28.16205 28.16205 28.16205 ZT8-11 27.4896 27.4896 27.4896 ZT12-15 0 0 0 ZT16-19 12.698599999999999 12.698599999999999 12.698599999999999 ZT20-23 23.50345 23.50345 23.50345