Many things driving the car loadings down. The low price of natural gas caused industries to shift from coal to gas. The low price of oil and gas has driven down new drilling, reducing shipments of steel, pipe and sand/drilling mud. The economy in the rest of the world is down, so they aren't ordering US goods, the price of the US dollar is high so the rest of the world isn't ordering as many US goods, the other oil based economies aren't getting oil revenue so they are having to sell off stocks to generate cash, forcing stock prices down. Nobody in the presidential campaign is encouraging the economy, all you hear is how bad the situation is (even though the numbers are much better than 2 or 3 years ago) so people have less confidence and buy less.