addition a significant portion of this increase was attributable to the introduction of new products, including our Votiva platform that launched in the third quarter of 2017. The increase was also attributable to an increase in our average selling prices in North America.
Our revenues in North America increased by approximately $26.4 million, or 146%, to approximately $44.6 million for the year ended December 31, 2017, compared to approximately $18.2 million for the year ended December 31, 2016. The increase was primarily attributable to the expansion of our direct sales organization, which increased sales in North America, the commercial launch of our Votiva platform, during the third quarter of 2017, and to an increase in our average selling prices in North America.
Our revenues in Europe increased by approximately $1.3 million, or 40%, to approximately $4.6 million for the year ended December 31, 2017, compared to approximately $3.3 million for the year ended December 31, 2016. The increase was primarily driven by the establishment of a direct sales team in the United Kingdom and Spain, which increased sales in those regions.
Our revenues from the sale of consumables and extended warranties for the year ended December 31, 2017 increased by approximately 115% compared to the year ended December 31, 2016. This increase was primarily attributable to the growth in our installed platform base, as well as patients and physicians becoming more familiar with our products.
Cost of Revenues. Our cost of revenues increased by approximately $3.4 million, or 60%, to approximately $9.1 million for the year ended December 31, 2017, compared to approximately $5.7 million for the year ended December 31, 2016. This increase was primarily due to increased costs to purchase manufactured products to support the higher sales volume. Our gross margin increased to approximately 83% for the year ended December 31, 2017, compared to approximately 76% for the year ended December 31, 2016, primarily due to the increase in our average selling prices in North America, as well as a higher percentage of revenue derived from North America as compared to other regions.
Research and Development Expenses. Our research and development expenses were relatively flat, increasing by approximately $0.1 million, or 5%, to approximately $2.6 million for the year ended December 31, 2017, compared to approximately $2.5 million for the year ended December 31, 2016.
Sales and Marketing Expenses. Our sales and marketing expenses increased by approximately $17.3 million, or 153%, to approximately $28.5 million for the year ended December 31, 2017, compared to approximately $11.3 million for the year ended December 31, 2016. This increase was primarily attributable to the expansion of our direct sales organization and an increase in variable compensation in North America.
General and Administrative Expenses. Our general and administrative expenses increased by approximately $1.3 million, or 43%, to approximately $4.4 million for the year ended December 31, 2017, compared to approximately $3.1 million for the year ended December 31, 2016. This increase was primarily attributable to increase in legal costs and expenses related to our litigation with Syneron-Candela.
Financial Income (Expense), Net. Our financial income expenses, net was approximately $0.8 million for the year ended December 31, 2017, compared to approximately $0.0 million for the year ended December 31, 2016. This increase in financial income, net was primarily attributable to an increase in interest earned on our long-term installment sales contracts with customers in North America and gain on foreign currency translation in the year ended December 31, 2017, as compared to a loss on foreign currency translation in the year ended December 31, 2016.
Income Tax. Our income taxes increased by approximately $0.6 million, or 191%, to approximately $1.0 million for the year ended December 31, 2017, compared to approximately $0.3 million for the year ended December 31, 2016. In 2017, the tax benefit derived from our “Benefited Enterprise” status was approximately $2.3 million, which represents approximately 23% of our income before taxes.
Selected Quarterly Results of Operations
The following table sets forth our unaudited consolidated quarterly results of operation for the periods indicated. You should read the following table in conjunction with our audited consolidated financial statements. We have prepared the unaudited consolidated quarterly financial information on the same basis