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NEW YORK ( TheStreet) -- How can investors determine what's really going on with the economy? Jim Cramer said on Mad Money Wednesday they should forget about using interest rates, commodity prices or the latest retail earnings for guidance. To learn how the economy is really doing, just look at Union Pacific (UNP) .
Cramer said when it comes to reading the economy, nothing offers a better picture than the transports, especially the rails. If it's being made, it needs to be shipped, Cramer continued, and that means Union Pacific, which reached an all-time high today.
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Just look at what Union Pacific ships, Cramer said: 20% of its earnings stems from intermodal shipments, while another 20% comes from industrial products, mainly materials used in housing like timber. Union Pacific also ships fracking sand, which gives investors a read on oil and energy. Then there are autos, coal and chemicals, which are all strong except for coal.Coal used to be a gauge of heavy industrial production and power generation, Cramer said, but with our country rapidly moving away from coal and towards natural gas, coal is no longer an indicator of anything in particular. So what does Union Pacific tell us? Cramer said the economy is strong and growing with continued low interest rates -- the perfect environment for stocks to go higher.