Cost of Revenues and Gross Profit. Cost of revenues includes the cost of hardware, quality assurance, overhead related to professional and support customer services, overhead related to manufacturing activity, technology licensing and royalty fees payable to third parties and to the IIA. Gross profit increased to $178.8 million in the year ended December 31, 2022, from $170.9 million in the year ended December 31, 2021. Gross profit as a percentage of total revenues was 65.0% in the year ended December 31, 2022, compared to 68.7% in the year ended December 31, 2021. The decrease in the gross profit as a percentage of total revenues is primarily attributable to higher supply chain costs on products and less favorable product mix. Expenses included in cost of revenues related to share-based compensation were $0.4 million in each of the years ended December 31, 2022 and 2021.
Cost of revenues related to sales of products increased by 20.7% to $63.7 million in the year ended December 31, 2022, from $52.8 million in the year ended December 31, 2021. Gross margin percentage from products was 61.2% in the year ended December 31, 2022 and 66.0% in the year ended December 31, 2021. This decrease is primarily attributable to higher supply chain costs and less favorable product mix.
Cost of revenues related to sales of services in the year ended December 31, 2022 increased by 29.1% to $32.6 million, from $25.3 million in the year ended December 31, 2021. This increase is primarily attributable to higher support personnel expenses associated with providing services and implementation of our products with service providers as well as enterprise customers. In the year ended December 31, 2022, the gross margin percentage from sales of services decreased to 70.5%, from 73.1% in the year ended December 31, 2021.
Research and Development Expenses, net. Research and development expenses, net, consist primarily of salaries and related costs of employees engaged in ongoing research and development activities, development-related raw materials and the cost of subcontractors, less grants from the IIA. Research and development expenses increased by 12.1% in the year ended December 31, 2022 to $59.8 million, from $53.4 million in the year ended December 31, 2021. As a percentage of total revenues, research and development expenses, net increased to 21.8% in the year ended December 31, 2022, from 21.5% in the year ended December 31, 2021. The increase on an absolute basis is primarily due to an increase in the total number of our employees and related expenses. In addition, in the year ended December 31, 2022, expenses included in research and development expenses related to share-based compensation were $3.5 million, compared to $2.8 million in the year ended December 31, 2021. IIA grants recognized were $0.6 million in each of the years ended December 31, 2022 and 2021.
Selling and Marketing Expenses. Selling and marketing expenses consist primarily of salaries and related costs (including sales commissions) of sales and marketing personnel, as well as exhibition, travel and related expenses. Selling and marketing expenses increased by 13.0% in the year ended December 31, 2022 to $70.1 million, from $62.1 million in the year ended December 31, 2021. As a percentage of total revenues, selling and marketing expenses increased to 25.5% in the year ended December 31, 2022, from 24.9% in the year ended December 31, 2021. The increase on an absolute basis is primarily due to an increase in the total number of our employees and related expenses associated with such employees. We added employees in an effort to increase our market share in the areas in which we sell our products and services, mainly due to our continued progress in pivoting to recurring revenues. In addition, in the year ended December 31, 2022, expenses included in selling and marketing expenses related to share-based compensation were $6.0 million, compared to $6.2 million in the year ended December 31, 2021.
General and Administrative Expenses. General and administrative expenses consist primarily of salaries and related costs of finance, human resources and general management personnel, rent, network and allowance for credit losses, as well as insurance and consultant services expenses. General and administrative expenses increased by 9.9% to $17.5 million in the year ended December 31, 2022, from $15.9 million in the year ended December 31, 2021. As a percentage of total revenues, general and administrative expenses were 6.4% in each of the years ended December 31, 2022 and 2021. The increase on an absolute basis is primarily due to an increase in payroll expenses. In addition, in the year ended December 31, 2022, expenses included in general and administrative expenses related to share-based compensation were $5.2 million compared to $4.8 million in the year ended December 31, 2021.
Financial Income (Expenses), Net. Financial income (expenses), net consists primarily of interest earned on cash and cash equivalents, marketable securities and bank deposits, gains from financial investments, net of interest on our bank loans and bank charges, exchange rate differences and linkage differences to the Israeli consumer price Index, or Israeli CPI, and amortization of marketable securities premiums and accretion of discounts, net. Financial income, net, in the year ended December 31, 2022 was $2.9 million, compared to financial income, net of $0.1 in the year ended December 31, 2021. The increase in financial expenses, net in the year ended December 31, 2022 was primarily due to (i) lower expenses related to exchange rate fluctuations; and (ii) higher interest income recorded with respect to marketable securities and financial investments.