condition mean min max ZT0-3 301.827277 301.827277 301.827277 ZT4-7 353.374159 353.374159 353.374159 ZT8-11 313.534592 313.534592 313.534592 ZT12-15 353.3193665 353.3193665 353.3193665 ZT16-19 298.0405485 298.0405485 298.0405485 ZT20-23 204.5294115 204.5294115 204.5294115