9/19/15: I use Mac with OS X 10.9.5 and Calander 7.0 and recently noticed that all my calendar events from previous years are gone. I do not have an iCloud account, do not want one, and am not interested in synching my desktop Mac calendar with other devices. I do not know what causes the elimination of last year's events, and do not find a Preference setting or other simple means of having my Calendar events saved across years. Thought that either CCCleaner or CleanMyMac, both of which I use frequently, might be clobbering my old Calendar events, but that does not appear to me to be the case. Any ideas?
Mac mini, OS X Mavericks (10.9.5), Calendar