condition mean min max ZT0-3 8.193975 8.093354999999999 8.294595000000001 ZT4-7 11.8932 11.8932 11.8932 ZT8-11 12.6158 12.6158 12.6158 ZT12-15 0 0 0 ZT16-19 12.114049999999999 12.114049999999999 12.114049999999999 ZT20-23 10.7024 10.7024 10.7024