CSX earnings have been hurt by the drop in coal shipments. CSX Corp. CSX 1.88 % on Tuesday reported revenue fell in the first quarter, as the volume of coal shipments, a key metric for railroads, dropped 31% to continue a trend that has hurt the top line for several quarters. In February, the Jacksonville, Fla., railroad said earnings in the latest quarter would drop significantly as the railroad expected volume to decline in the mid-to-high single digits. On Tuesday, CSX reported that total volume was down 5% for the quarter. CSX expects coal volume to decline more than 20% in 2016 and see most other markets also declining year-over-year. Some 20% of CSX’s revenue last year came from coal versus an industry average of about 15%. The company has responded by cutting costs, laying off workers and mothballing railcars. CSX’s stock has rebounded some 16% from a three-year […]