condition mean min max ZT0-3 2.18993 1.0740750000000001 3.49877 ZT4-7 2.798895 2.798895 2.798895 ZT8-11 3.4501 3.4501 3.4501 ZT12-15 5.983035 4.35186 7.61421 ZT16-19 3.06421 3.06421 3.06421 ZT20-23 2.8467450000000003 2.8467450000000003 2.8467450000000003