condition mean min max ZT0-3 22.704136 22.704136 22.704136 ZT4-7 25.8790355 25.8790355 25.8790355 ZT8-11 24.239399 24.239399 24.239399 ZT12-15 23.0482035 23.0482035 23.0482035 ZT16-19 22.584162 22.584162 22.584162 ZT20-23 24.713415 24.713415 24.713415