condition mean min max ZT0-3 4.258506666666666 0.573365 10.445665 ZT4-7 3.876645 3.876645 3.876645 ZT8-11 1.8119450000000001 1.8119450000000001 1.8119450000000001 ZT12-15 0.95136175 0.9232564999999999 0.979467 ZT16-19 0.451111 0.451111 0.451111 ZT20-23 0.1003025 0.1003025 0.1003025