condition mean min max ZT0-3 0.29994966666666667 0.172039 0.542934 ZT4-7 0.3428325 0.3428325 0.3428325 ZT8-11 0.3540375 0.3540375 0.3540375 ZT12-15 0.48437149999999995 0.392063 0.57668 ZT16-19 0.3301165 0.3301165 0.3301165 ZT20-23 0.3863215 0.3863215 0.3863215