condition mean min max ZT0-3 4.428765 3.9186750000000004 4.938855 ZT4-7 5.5574650000000005 5.5574650000000005 5.5574650000000005 ZT8-11 17.0086 17.0086 17.0086 ZT12-15 0 0 0 ZT16-19 13.892 13.892 13.892 ZT20-23 11.471350000000001 11.471350000000001 11.471350000000001