condition mean min max ZT0-3 1.5849029570000002 0.9732585770000001 2.196547337 ZT4-7 3.58435521925 2.9133587745 4.255351664 ZT8-11 4.807733504750001 4.2395998185 5.375867191 ZT12-15 9.11297641 7.877339528 10.348613292 ZT16-19 9.6236065585 8.802960177 10.44425294 ZT20-23 16.348965865 14.706294215 17.991637515