condition mean min max ZT0-3 23.635350000000003 23.635350000000003 23.635350000000003 ZT4-7 13.80795 13.80795 13.80795 ZT8-11 14.090900000000001 14.090900000000001 14.090900000000001 ZT12-15 18.059 18.059 18.059 ZT16-19 32.267450000000004 32.267450000000004 32.267450000000004 ZT20-23 32.3667 32.3667 32.3667