condition mean min max ZT0-3 7.682922499999999 6.7380949999999995 8.627749999999999 ZT4-7 1.0833045 1.0833045 1.0833045 ZT8-11 2.275 2.275 2.275 ZT12-15 0 0 0 ZT16-19 14.502565 14.502565 14.502565 ZT20-23 0.194972 0.194972 0.194972