condition mean min max ZT0-3 3.612515 3.57866 3.64637 ZT4-7 1.763305 1.763305 1.763305 ZT8-11 1.140307 1.140307 1.140307 ZT12-15 0 0 0 ZT16-19 2.34994 2.34994 2.34994 ZT20-23 1.988245 1.988245 1.988245