pre_text: Results of Operations We operate a cybersecurity business, focused on licensing and enforcement, providing advisory services, developing mobile security applications, and investing in emerging cybersecurity technologies and intellectual property. The following table summarizes our results of operations for the periods presented and as a percentage of our total revenue for those periods based on our consolidated statement of operations data. The year to year comparison of results of operations is not necessarily indicative of results of operations for future periods.
table: For the Years Ended December 31,
table: 2019 2018 2017
table: Amount % of Revenue Amount % of Revenue Amount % of Revenue
table: (In millions, except percentages)
table: Revenues $13.2 100% $82.3 100% $50.5 100%
table: Cost of revenues 1.9 14% 15.3 19% 6.0 12%
table: Gross profit 11.3 86% 67.0 81% 44.5 88%
table: Operating expenses:
table: Selling, general and administrative (1) 31.7 240% 32.2 39% 28.6 57%
table: Research and development 2.0 15% 2.1 2% 1.5 3%
table: Total operating expenses 33.7 225% 34.3 41% 30.1 60%
table: Other income (expense) (0.3) (2)% (4.0) (5)% 2.2 4%
table: Income (loss) before income taxes (22.7) (172%) 28.7 35% 16.6 33%
table: Income tax provision (benefit) (6.2) (47%) 8.0 10% (6.2) (12)%
table: Net income (loss) $(16.5) (125)% $20.7 25% $22.8 45%
table: (1) Includes stock based compensation $1.0 8% $1.6 2% $0.8 2%
question: Analyse this data from a financial earnings document. What is the average revenue between 2017 to 2019?