condition mean min max ZT0-3 8.948263 8.948263 8.948263 ZT4-7 10.215343 10.215343 10.215343 ZT8-11 12.464408 12.464408 12.464408 ZT12-15 10.5331265 10.5331265 10.5331265 ZT16-19 8.974404 8.974404 8.974404 ZT20-23 9.918503000000001 9.918503000000001 9.918503000000001