condition mean min max ZT0-3 6.2168600000000005 6.2168600000000005 6.2168600000000005 ZT4-7 4.525225 4.525225 4.525225 ZT8-11 4.921245 4.921245 4.921245 ZT12-15 7.7762899999999995 7.7762899999999995 7.7762899999999995 ZT16-19 10.100249999999999 10.100249999999999 10.100249999999999 ZT20-23 7.440305 7.440305 7.440305