condition mean min max ZT0-3 17.117566666666665 12.51455 25.35455 ZT4-7 16.77645 16.77645 16.77645 ZT8-11 9.428145 9.428145 9.428145 ZT12-15 17.3486 15.11195 19.585250000000002 ZT16-19 12.1783 12.1783 12.1783 ZT20-23 11.975349999999999 11.975349999999999 11.975349999999999