condition mean min max ZT0-3 7.848523 7.848523 7.848523 ZT4-7 7.520804 7.520804 7.520804 ZT8-11 7.631857500000001 7.631857500000001 7.631857500000001 ZT12-15 8.444417 8.444417 8.444417 ZT16-19 7.7457135 7.7457135 7.7457135 ZT20-23 8.013487 8.013487 8.013487