condition mean min max ZT0-3 11.972923333333332 8.13702 14.3432 ZT4-7 8.51543 8.51543 8.51543 ZT8-11 7.498555 7.498555 7.498555 ZT12-15 9.1355975 9.03847 9.232725 ZT16-19 8.94663 8.94663 8.94663 ZT20-23 14.155899999999999 14.155899999999999 14.155899999999999