condition mean min max ZT0-3 0.31908575000000006 0.29188800000000004 0.3462835 ZT4-7 0.245313 0.245313 0.245313 ZT8-11 0.25017665 0.25017665 0.25017665 ZT12-15 0 0 0 ZT16-19 0.48605349999999997 0.48605349999999997 0.48605349999999997 ZT20-23 0.538392 0.538392 0.538392