condition mean min max ZT0-3 4.727165 4.727165 4.727165 ZT4-7 5.7828 5.7828 5.7828 ZT8-11 1.27684 1.27684 1.27684 ZT12-15 1.185408 1.185408 1.185408 ZT16-19 3.076785 3.076785 3.076785 ZT20-23 4.169045 4.169045 4.169045