condition mean min max ZT0-3 4.155095 4.155095 4.155095 ZT4-7 4.85375 4.85375 4.85375 ZT8-11 5.318275 5.318275 5.318275 ZT12-15 2.91212 2.91212 2.91212 ZT16-19 5.228345 5.228345 5.228345 ZT20-23 4.31079 4.31079 4.31079