Amazon’s merchandise sales appear to have grown as much as two times faster as online retail sales as a whole did in the United States in the fourth quarter, according to financial results released by the company Thursday.

Amazon reported its sales of electronics and other general merchandise – not including music, books, video and other media products – reached $10.6 billion in North America during the quarter, up 25.2 percent compared with the same quarter a year earlier. By comparison, total online retail sales increased 10.3 percent in the United States during the fourth quarter, according to an estimate by IBM Digital Analytics Benchmark.
 
Amazon reported its international sales of electronics and other general merchandise reached $6.48 billion, up 19.2 percent. Excluding the effect of exchange rates, those sales grew 21 percent.
 
Tellingly, electronics and general merchandize sales increased from 65 to 67 percent of Amazon’s fourth quarter sales.
Amazon reported operating income increased 26 percent to $510 million in the fourth quarter, compared with $405 million in fourth quarter 2012. The favorable impact from year-over-year changes in foreign exchange rates throughout the quarter on operating income was $7 million. Net income increased to $239 million in the fourth quarter, or $0.51 per diluted share, compared with $97 million, or $0.21 per diluted share, in fourth quarter 2012.
 
The company generated free cash flow of $2.03 billion during the 12 months ended Dec. 31, 2013, compared with $395 million for the 12 months ended Dec. 31, 2012. Free cash flow for the trailing twelve months ended December 31, 2012 includes fourth quarter cash outflows for purchases of corporate office space and property in Seattle, Washington, of $1.4 billion.