I spent the morning replacing old door knobs and power outlets around the house. These items were purchased from both Lowe’s and Home Depot — America’s two retail home improvement giants. The stores in our neighborhood are next to one another, and I sometimes can’t decide which one to choose.

Perhaps investors feel the same way? This interactive chart, made with Google’s finance service, shows both companies’ movement on the New York Stock Exchange since Jan. 4, 2008. Lowe’s is blue; Home Depot is red. Notice that they fall and climb at similar times: 

You might think that these spikes and dips relate closely to the performance of the Dow Jones Industrial Average. The two companies follow the trend generally, but they rise and fall together: 

Perhaps this has to do with the price of lumber or something. Thoughts? 

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