condition mean min max ZT0-3 5.391418333333333 5.143 5.645255 ZT4-7 3.850105 3.850105 3.850105 ZT8-11 6.85849 6.85849 6.85849 ZT12-15 10.828872500000001 10.14835 11.509395000000001 ZT16-19 8.412825 8.412825 8.412825 ZT20-23 8.50487 8.50487 8.50487