condition mean min max ZT0-3 34.6 34.6 34.6 ZT4-7 67.5 67.5 67.5 ZT8-11 69.19999999999999 69.19999999999999 69.19999999999999 ZT12-15 56.949999999999996 56.949999999999996 56.949999999999996 ZT16-19 41.099999999999994 41.099999999999994 41.099999999999994 ZT20-23 24.2 24.2 24.2