condition mean min max ZT0-3 8.9897225 8.432855 9.54659 ZT4-7 6.291255 6.291255 6.291255 ZT8-11 7.523605 7.523605 7.523605 ZT12-15 0 0 0 ZT16-19 7.87068 7.87068 7.87068 ZT20-23 8.79016 8.79016 8.79016