condition mean min max ZT0-3 2.4811725 2.0526 2.909745 ZT4-7 0.7605139999999999 0.7605139999999999 0.7605139999999999 ZT8-11 0.5990025 0.5990025 0.5990025 ZT12-15 0 0 0 ZT16-19 1.8419400000000001 1.8419400000000001 1.8419400000000001 ZT20-23 2.165915 2.165915 2.165915