condition mean min max ZT0-3 55.524535 55.524535 55.524535 ZT4-7 67.1589315 67.1589315 67.1589315 ZT8-11 74.5053605 74.5053605 74.5053605 ZT12-15 66.216542 66.216542 66.216542 ZT16-19 89.7074295 89.7074295 89.7074295 ZT20-23 78.594626 78.594626 78.594626