condition mean min max ZT0-3 10.829067 10.829067 10.829067 ZT4-7 9.752426 9.752426 9.752426 ZT8-11 10.171109 10.171109 10.171109 ZT12-15 8.8952925 8.8952925 8.8952925 ZT16-19 9.7409695 9.7409695 9.7409695 ZT20-23 9.7310775 9.7310775 9.7310775