condition mean min max ZT0-3 3.86754 3.86754 3.86754 ZT4-7 3.66317 3.66317 3.66317 ZT8-11 4.894444999999999 4.894444999999999 4.894444999999999 ZT12-15 5.336835000000001 5.336835000000001 5.336835000000001 ZT16-19 4.31096 4.31096 4.31096 ZT20-23 3.723155 3.723155 3.723155