condition mean min max ZT0-3 5.641505 5.641505 5.641505 ZT4-7 4.428095000000001 4.428095000000001 4.428095000000001 ZT8-11 4.23607 4.23607 4.23607 ZT12-15 5.393435 5.393435 5.393435 ZT16-19 6.000735 6.000735 6.000735 ZT20-23 5.5162700000000005 5.5162700000000005 5.5162700000000005