condition mean min max ZT0-3 12.5702 12.5702 12.5702 ZT4-7 10.75535 10.75535 10.75535 ZT8-11 5.373585 5.373585 5.373585 ZT12-15 6.806385 6.806385 6.806385 ZT16-19 8.383195 8.383195 8.383195 ZT20-23 12.505749999999999 12.505749999999999 12.505749999999999