condition mean min max ZT0-3 11.908075 11.908075 11.908075 ZT4-7 13.827721 13.827721 13.827721 ZT8-11 12.8936175 12.8936175 12.8936175 ZT12-15 11.446256 11.446256 11.446256 ZT16-19 12.43557 12.43557 12.43557 ZT20-23 11.1913595 11.1913595 11.1913595