condition mean min max ZT0-3 284.793727 284.793727 284.793727 ZT4-7 234.2016645 234.2016645 234.2016645 ZT8-11 283.60418000000004 283.60418000000004 283.60418000000004 ZT12-15 281.462826 281.462826 281.462826 ZT16-19 245.34942 245.34942 245.34942 ZT20-23 262.4116525 262.4116525 262.4116525