condition mean min max ZT0-3 958.108185 958.108185 958.108185 ZT4-7 1065.2251315 1065.2251315 1065.2251315 ZT8-11 1004.416865 1004.416865 1004.416865 ZT12-15 725.3479115 725.3479115 725.3479115 ZT16-19 737.4311700000001 737.4311700000001 737.4311700000001 ZT20-23 781.0839404999999 781.0839404999999 781.0839404999999