condition mean min max ZT0-3 4.468325 4.468325 4.468325 ZT4-7 3.537745 3.537745 3.537745 ZT8-11 4.1783 4.1783 4.1783 ZT12-15 4.798235 4.798235 4.798235 ZT16-19 5.803929999999999 5.803929999999999 5.803929999999999 ZT20-23 4.60473 4.60473 4.60473