condition mean min max ZT0-3 4.184835 4.184835 4.184835 ZT4-7 1.84476 1.84476 1.84476 ZT8-11 3.808335 3.808335 3.808335 ZT12-15 6.35472 6.35472 6.35472 ZT16-19 8.574449999999999 8.574449999999999 8.574449999999999 ZT20-23 5.6615 5.6615 5.6615