condition mean min max ZT0-3 13.529288 13.529288 13.529288 ZT4-7 14.097547 14.097547 14.097547 ZT8-11 12.15109 12.15109 12.15109 ZT12-15 11.450891500000001 11.450891500000001 11.450891500000001 ZT16-19 11.618471 11.618471 11.618471 ZT20-23 12.088531 12.088531 12.088531