condition mean min max ZT0-3 4.99705 4.1945749999999995 5.799525 ZT4-7 7.15498 7.15498 7.15498 ZT8-11 6.326585 6.326585 6.326585 ZT12-15 0 0 0 ZT16-19 7.942259999999999 7.942259999999999 7.942259999999999 ZT20-23 10.25205 10.25205 10.25205