1st question, How is AutoTraders overall business doing? (how hard are they working for us?)
See national trend for AutoTrader Google Trends: autotrader Look at the chart, you'll see VERY VERY STRONG GROWTH.
Ok., so so we can see people that go to Google and type in AutoTrader is trending strongly. It's not an exaggeration to say it's WAY UP. Does that translate into more VDPs nation wide? For some reason, They won't let me look at their records 
2nd question, your 3 year chart is trending lower... or is it?
Compare the last 3 years of the google national chart above against your 3 year chart. Google Chart UP, your chart DOWN. We can assume that it's likely you're looking at a local marketplace problem.
Lets look a lil' harder at your chart. Compare your MARCH PEAKS. Notice the extra soft 2010 peak. 2011 is greater than 2010.
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Thought #1. Your spring 2010 performance was very weak and could easily cause your trendline to point lower. See spring 2008 vs spring 2011, very similar. 2009 was very strong, but not strong enough to offset the godawful 2010 numbers.
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Thought #2. Your market may have hit bottom. Spring 2011 was CLEARLY way better than 2010
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Also, can't get too granular with this, consider the smaller the data measured, the more erratic it becomes.
