condition mean min max ZT0-3 14.274456 14.274456 14.274456 ZT4-7 13.071639999999999 13.071639999999999 13.071639999999999 ZT8-11 11.824032500000001 11.824032500000001 11.824032500000001 ZT12-15 12.5597805 12.5597805 12.5597805 ZT16-19 12.052337 12.052337 12.052337 ZT20-23 12.592682 12.592682 12.592682