condition mean min max ZT0-3 10.829067 10.829067 10.829067 ZT4-7 10.55961 10.55961 10.55961 ZT8-11 12.898276 12.898276 12.898276 ZT12-15 10.7212415 10.7212415 10.7212415 ZT16-19 12.5551825 12.5551825 12.5551825 ZT20-23 12.091093 12.091093 12.091093