You can upload all the entries for a given category as a spreadsheet to Google Docs or email them as .CSV file to be opened with Excel or other popular spreadsheet application.
To export categories as spreadsheets, tap on the info button in the lower right corner (on the main page) and navigate to Settings -> Desktop Data Transfer -> Export a Spreadsheet.
To export a category as a CSV file, navigate to the Year view and tap on the Command button located in the top right corner.
