condition mean min max ZT0-3 4.690458666666667 0.6811075 12.204550000000001 ZT4-7 8.788910000000001 8.788910000000001 8.788910000000001 ZT8-11 3.7975000000000003 3.7975000000000003 3.7975000000000003 ZT12-15 3.7463035 1.058387 6.43422 ZT16-19 1.446075 1.446075 1.446075 ZT20-23 1.148834 1.148834 1.148834