condition mean min max ZT0-3 10.39179 9.567730000000001 11.21585 ZT4-7 8.531054999999999 8.531054999999999 8.531054999999999 ZT8-11 10.4909 10.4909 10.4909 ZT12-15 0 0 0 ZT16-19 14.686350000000001 14.686350000000001 14.686350000000001 ZT20-23 12.6573 12.6573 12.6573