85/264 Research and development Research and development expenses increased in each period presented, due to our continual enhancement of our platform in order to retain and grow our User base, with an exception for the quarter ended September 30, 2016, which remained relatively flat. The increases in all other quarterly periods were due principally to increases in personnel­related and facilities costs resulting from increased headcount and leased office space to support our growth. Sales and marketing Our sales and marketing spend increased in the second and fourth quarter of each year in line with our seasonal campaign offerings. The quarterly periods presented increased year over year due principally to incremental advertising and marketing spend and promotional campaigns in existing markets as well as new markets. There also were increases in personnel­related and facilities costs, each resulting from increased headcount and leased office space to support our growth for each of the quarterly periods presented. General and administrative Except for a decrease in the quarters ended September 30, 2016 and 2017, general and administrative expenses increased throughout the periods presented. The increases in all other quarterly periods were due principally to increases in personnel­related and facilities costs, resulting from increased headcount and leased office space to support our growth. We also experienced an increase in legal and other administrative costs due to increased litigation, consulting costs related to public company readiness objectives, new systems implementations, and commissions paid for new leases. Finance income There were no significant unusual movements in finance income, with the exception of the fourth quarter of 2016. In the fourth quarter of 2016, we recognized foreign exchange gains of €96 million on the remeasurement of monetary assets, principally our short term investments, due to advantageous movements between the U.S. Dollar and Euro exchange rate. The fair value gains recorded on our contingent options increased throughout the periods in line with the increase in the fair value of our ordinary shares. Additionally, there was an increase in interest income reflecting our increase in short term investments. Finance costs Finance costs trended higher over the periods presented due principally to the issuance of the Convertible Notes in second quarter of 2016 and the issuance of warrants in the fourth quarter of 2016 and the third quarter of 2017. These financial liabilities were accounted for at fair value with any changes in fair value recorded in the statement of operations. The fair value adjustments recorded on our Convertible Notes and warrants have increased throughout the periods in line with the increase in the fair value of our ordinary shares and the implicit interest of the Convertible Notes. Additionally, foreign exchange losses on the remeasurement of monetary assets and liabilities in a transaction currency other than the functional currency increased, related principally to our U.S. Dollar short term investments. 78