condition mean min max ZT0-3 11.773564 11.773564 11.773564 ZT4-7 10.872084000000001 10.872084000000001 10.872084000000001 ZT8-11 10.1958925 10.1958925 10.1958925 ZT12-15 10.8455585 10.8455585 10.8455585 ZT16-19 10.809966 10.809966 10.809966 ZT20-23 12.6945805 12.6945805 12.6945805