condition mean min max ZT0-3 1.3868550000000002 1.33631 1.4374 ZT4-7 1.61869 1.61869 1.61869 ZT8-11 1.75267 1.75267 1.75267 ZT12-15 0 0 0 ZT16-19 2.297365 2.297365 2.297365 ZT20-23 1.6400350000000001 1.6400350000000001 1.6400350000000001