condition mean min max ZT0-3 1.612725 1.612725 1.612725 ZT4-7 3.575 3.575 3.575 ZT8-11 1.944515 1.944515 1.944515 ZT12-15 0.507605 0.507605 0.507605 ZT16-19 1.350255 1.350255 1.350255 ZT20-23 1.99319 1.99319 1.99319