condition mean min max ZT0-3 2794.152283 2794.152283 2794.152283 ZT4-7 3535.2275945 3535.2275945 3535.2275945 ZT8-11 3322.496766 3322.496766 3322.496766 ZT12-15 3796.788301 3796.788301 3796.788301 ZT16-19 2963.3103725 2963.3103725 2963.3103725 ZT20-23 2394.885256 2394.885256 2394.885256