condition mean min max ZT0-3 24.9658 24.9658 24.9658 ZT4-7 13.57555 13.57555 13.57555 ZT8-11 9.481785 9.481785 9.481785 ZT12-15 14.21705 14.21705 14.21705 ZT16-19 23.41225 23.41225 23.41225 ZT20-23 26.59815 26.59815 26.59815