condition mean min max ZT0-3 3.3063525 2.929675 3.68303 ZT4-7 3.4591849999999997 3.4591849999999997 3.4591849999999997 ZT8-11 4.931615 4.931615 4.931615 ZT12-15 0 0 0 ZT16-19 4.45297 4.45297 4.45297 ZT20-23 3.814715 3.814715 3.814715