condition mean min max ZT0-3 25.382325 24.6691 26.095550000000003 ZT4-7 12.64705 12.64705 12.64705 ZT8-11 8.5595 8.5595 8.5595 ZT12-15 0 0 0 ZT16-19 14.57335 14.57335 14.57335 ZT20-23 22.18505 22.18505 22.18505