condition mean min max ZT0-3 10.628863 10.628863 10.628863 ZT4-7 11.169756 11.169756 11.169756 ZT8-11 12.644925 12.644925 12.644925 ZT12-15 12.791217 12.791217 12.791217 ZT16-19 10.099988499999998 10.099988499999998 10.099988499999998 ZT20-23 11.275175999999998 11.275175999999998 11.275175999999998