condition mean min max ZT0-3 9.561127500000001 9.486335 9.63592 ZT4-7 18.79785 18.79785 18.79785 ZT8-11 17.57365 17.57365 17.57365 ZT12-15 0 0 0 ZT16-19 10.609395 10.609395 10.609395 ZT20-23 10.38635 10.38635 10.38635