condition mean min max ZT0-3 12.172321 12.172321 12.172321 ZT4-7 11.985573 11.985573 11.985573 ZT8-11 11.7127895 11.7127895 11.7127895 ZT12-15 11.6389125 11.6389125 11.6389125 ZT16-19 11.554434 11.554434 11.554434 ZT20-23 12.1773215 12.1773215 12.1773215