condition mean min max ZT0-3 11.76844 11.13533 12.40155 ZT4-7 16.4934 16.4934 16.4934 ZT8-11 20.42465 20.42465 20.42465 ZT12-15 0 0 0 ZT16-19 22.90015 22.90015 22.90015 ZT20-23 21.58325 21.58325 21.58325