condition mean min max ZT0-3 11.038749 11.038749 11.038749 ZT4-7 11.3549535 11.3549535 11.3549535 ZT8-11 9.881776 9.881776 9.881776 ZT12-15 8.910873 8.910873 8.910873 ZT16-19 9.6956095 9.6956095 9.6956095 ZT20-23 10.6328765 10.6328765 10.6328765