Yesterday I had 9200-ish reputation on Area 51. Today 7576. I don't see any dramatic changes for other users. The reputation link implies I've never had more than 7576 reputation.
Edit: is @Lennart right? Can rep be lost when proposals are deleted? Seems strange that, e.g. the right to edit posts can be gained (when 1000 rep is achieved) and then lost simply because proposals are deleted. I thought you only lose rep when you "spend" it (by downvoting) or incur the wrath of moderators (by bad behaviour).
Follow up question: Should reputation on a failed proposal be retained?