condition mean min max ZT0-3 9.8415125 9.574919999999999 10.108105 ZT4-7 8.51422 8.51422 8.51422 ZT8-11 9.424645 9.424645 9.424645 ZT12-15 0 0 0 ZT16-19 11.93385 11.93385 11.93385 ZT20-23 11.7576 11.7576 11.7576