According to the performance report for June, UP loaded 921 trains in the SPRB compared with 881 trains in the corresponding month last year. The average per day was 30.7 trains compared to 28.9 in May 2010.

There were 105 missed loading opportunities, 26 of which were attributable to the company. Sixty three missed loadings were attributable to utility plants, 16 to mines and 13 to flooding or severe weather.

UP, which works primarily in the western US coalfields, was able to offset some of that loss by logging 96 extra loadings in June, according to the report.

In its other primary area of coalfield operations, the Colorado/Utah region, UP loaded 211 coal trains in June compared with 213 in June 2009 and 191 in May.

In May, UP logged 896 loaded trains from the SPRB compared with 887 in the comparable month in 2009.

In the Colorado/Utah region, the total was 191 compared with 193 year-on-year, though the company said customer maintenance outages and higher stockpiles were to blame for the outcome.

Also in May, UP had 106 missed loading opportunities, but made up for the shortage by taking 103 extra loads that month.