condition mean min max ZT0-3 1439.654257 1439.654257 1439.654257 ZT4-7 1578.3129545000002 1578.3129545000002 1578.3129545000002 ZT8-11 739.3877594999999 739.3877594999999 739.3877594999999 ZT12-15 426.586709 426.586709 426.586709 ZT16-19 178.0823805 178.0823805 178.0823805 ZT20-23 329.4834265 329.4834265 329.4834265