condition mean min max ZT0-3 12.549999999999999 12.549999999999999 12.549999999999999 ZT4-7 11.8 11.8 11.8 ZT8-11 15.5 15.5 15.5 ZT12-15 11.75 11.75 11.75 ZT16-19 4.65 4.65 4.65 ZT20-23 10.600000000000001 10.600000000000001 10.600000000000001