Calendar Summary
Calendar Summary for Mac can summarize events from your calendars in text form. The text can then be saved to a file or copied into another application.
The motivation for Calendar Summary was to extract information from calendars for use in tax return preparation, so the summary text is formatted into tab-separated columns that can be easily imported or copied into applications such as Apple's Numbers or Microsoft Excel.
Calendar Summary works with any calendar application that uses Apple's calendar/event data store (EventKit); e.g., Calendar (formerly iCal).