From GigaOM

Parking Lots Help Predict Earnings: “”

UBS Investment Research has started incorporating analysis of satellite images of the parking lots of big-box retailers into its earnings estimates, reports CNBC, forecasting an uptick in sales based on parking lot traffic where a drop was previously expected.

I imagine one could do the same with Traffic Counts for the economy as a whole, without requiring satellites, though it would not be store-specific.