condition mean min max ZT0-3 327.080584 327.080584 327.080584 ZT4-7 262.464315 262.464315 262.464315 ZT8-11 259.215673 259.215673 259.215673 ZT12-15 262.537871 262.537871 262.537871 ZT16-19 200.6829035 200.6829035 200.6829035 ZT20-23 223.544038 223.544038 223.544038