The $0.1 million, or 0.5%, decline in net revenue during the three months ended December 31, 2013 primarily reflects the impact of a reduction in political advertising compared with the same period in 2012.
Lower net revenue in the 2013 fourth quarter and a $0.4 million, or 2.5%, increase in station operating expenses related to operating KVGS-FM in Las Vegas which was acquired in September 2013, as well as a rise in sales and programming expenses, caused fourth quarter 2013 station operating income (SOI), a non-GAAP financial measure, to decrease by $0.6 million, or 5.2%, to $10.2 million, as compared to the 2012 fourth quarter. The $0.7 million, or 8.3% year-over-year reduction in 2013 fourth quarter operating income is primarily attributable to the year-over-year revenue decline and a $0.5 million or 2.7% increase in total operating expenses compared with fourth quarter 2012 levels.
