condition mean min max ZT0-3 18.614093 18.614093 18.614093 ZT4-7 18.0020775 18.0020775 18.0020775 ZT8-11 13.698342 13.698342 13.698342 ZT12-15 16.252172 16.252172 16.252172 ZT16-19 16.930660500000002 16.930660500000002 16.930660500000002 ZT20-23 23.631098 23.631098 23.631098