Based on Jryoung's idea to look at deer tags, I went ahead and plotted other tags.
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Also, since CA has more US military personnel than any other state, and almost certainly, many of those are transplants from other states, I plotted total military over time (could not find CA only data). Also I added DFW's deer population estimates in there.
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I dont see any single smoking gun. It looks like a whole bunch of effects going on.
I guess looking at other states would give us a clue if this is really a CA state issue, or a national issue.
I tried to attach the file for others to play with, but the site wont let me attach a .xls