cleaning and supplies. This expense increased year-over-year primarily due to costs associated with enhancements to our onboard product offering and the 3.3% increase in traffic.

Other. Other operating expense increased primarily due to costs associated with sales of non-jet fuel products to third parties by our oil refinery.

Results of Operations - 2014 Compared to 2013

Operating Revenue

Passenger Revenue

Passenger revenue increased $2.0 billion, or 6.1%, over prior year. PRASM increased 3.0% and passenger mile yield increased 2.0% on 3.0% higher capacity. Load factor was 0.9 points higher than prior year at 84.7%.

Our geographic regions generally performed well compared to the prior year, with the domestic region leading year-over-year unit revenue improvement. Unit revenues of the domestic region rose 5.2% led by strong performances from our hubs in Atlanta, New York-LaGuardia and Seattle.

Revenues related to our international regions increased 3.0% year-over-year primarily due to 17.7% capacity growth in the Latin America region as a result of our efforts to improve connections with GOL and Aeroméxico. GOL and Aeroméxico contributed a significant portion of the traffic from the U.S. to Brazil and into key Mexico markets, respectively. Despite these contributions, Latin America unit revenues declined 2.5% as a result of the capacity increase, some business demand weakness associated with the FIFA World Cup in Brazil and economic concerns in Venezuela. Atlantic unit revenue increased 2.1% driven by yield improvements. While our joint venture with Virgin Atlantic reflected solid revenue growth, especially in London-Heathrow, Atlantic yields experienced pressure from the impact of geopolitical and health concerns related to service to Africa, the Middle East and Russia. Our Pacific region experienced a 3.8% decline in unit revenues driven by lower yield, primarily due to the weakening of the Japanese yen.

Other Revenue. Other revenue increased $580 million, or 14.9%, primarily due to an increase in sales of SkyMiles, settlements associated with our transatlantic joint venture agreements and sales of non-jet fuel products to third parties by our oil refinery.

Operating Expense	

Salaries and Related Costs . The increase in salaries and related costs is primarily due to investments in our employees and an increase in pilot and flight attendant block hours, partially offset by lower pension expense.

Fuel Expense. Compared to the prior year, consolidated fuel expense increased $2.0 billion due to unfavorable MTM adjustments on fuel hedges resulting from the significant decrease in crude oil prices during the year (from a high of $115 per barrel in June to a low of $57 per barrel at December 31, 2014) and a 1.7% increase in consumption, partially offset by a 7.8% decrease in fuel market price per gallon and increased profitability at Monroe. The table below presents fuel expense, gallons consumed and our average price per gallon, including the impact of hedging and the refinery:

Regional Carriers Expense. The reduction in regional carriers expense is primarily due to lower fuel expense from both a decrease in the cost of fuel per