condition mean min max ZT0-3 1.8720675 1.73284 2.011295 ZT4-7 1.616755 1.616755 1.616755 ZT8-11 2.4768800000000004 2.4768800000000004 2.4768800000000004 ZT12-15 0 0 0 ZT16-19 2.87752 2.87752 2.87752 ZT20-23 2.3721550000000002 2.3721550000000002 2.3721550000000002