condition mean min max ZT0-3 0.964811 0.964811 0.964811 ZT4-7 0.7389665 0.7389665 0.7389665 ZT8-11 1.35467 1.35467 1.35467 ZT12-15 1.2055354999999999 1.2055354999999999 1.2055354999999999 ZT16-19 1.56442 1.56442 1.56442 ZT20-23 0.905383 0.905383 0.905383