condition mean min max ZT0-3 12.010695 10.53744 13.48395 ZT4-7 4.855375 4.855375 4.855375 ZT8-11 4.45714 4.45714 4.45714 ZT12-15 0 0 0 ZT16-19 9.53261 9.53261 9.53261 ZT20-23 12.68535 12.68535 12.68535