condition mean min max ZT0-3 15.91892 15.91892 15.91892 ZT4-7 16.711187 16.711187 16.711187 ZT8-11 14.8217865 14.8217865 14.8217865 ZT12-15 14.1693655 14.1693655 14.1693655 ZT16-19 15.526474499999999 15.526474499999999 15.526474499999999 ZT20-23 14.418637 14.418637 14.418637