condition mean min max ZT0-3 2.35386 2.140595 2.673175 ZT4-7 2.542105 2.542105 2.542105 ZT8-11 1.6752500000000001 1.6752500000000001 1.6752500000000001 ZT12-15 1.56007725 0.8372545 2.2829 ZT16-19 1.371025 1.371025 1.371025 ZT20-23 1.9575 1.9575 1.9575