condition mean min max ZT0-3 4.68749 3.826925 6.313610000000001 ZT4-7 9.546895 9.546895 9.546895 ZT8-11 5.701985 5.701985 5.701985 ZT12-15 10.349725 8.425550000000001 12.2739 ZT16-19 6.21266 6.21266 6.21266 ZT20-23 6.516500000000001 6.516500000000001 6.516500000000001