condition mean min max ZT0-3 20.421425 20.2467 20.59615 ZT4-7 16.00225 16.00225 16.00225 ZT8-11 8.546009999999999 8.546009999999999 8.546009999999999 ZT12-15 0 0 0 ZT16-19 12.378555 12.378555 12.378555 ZT20-23 11.847684999999998 11.847684999999998 11.847684999999998