We expanded the Open Graph to include more types of sharing activities in the first quarter of 2012. If any of the following risks actually occurs, our business, financial condition, results of operations, and future prospects could be materially and adversely affected. Contains the proposed title of the dissertation, the candidate's full name, the names of all committee members, and the name and signature of the candidate's Supervisory Committee Chair. Many of these laws and regulations are subject to change and uncertain interpretation, and could result in claims, changes to our business practices, increased cost of operations, or declines in user growth or engagement, or otherwise harm our business. The forfeiture rate is derived primarily from our historical data, and the risk-free interest rate is based on the yield available on U. In addition, if we fail to successfully integrate any acquisitions, or the technologies associated with such acquisitions, into our company, the revenue and operating results of the combined company could be adversely affected. Move Fast Moving fast enables us to build more things and learn faster.
For example, we place a session cookie on your computer each time you visit our Website. Facebook also enables you to discover whats going on in the world around you, through the eyes and ears of people you trust. Advertising revenue grew due to a 42% increase in the number of ads delivered and an 18% increase in the average price per ad delivered. In September 2011, at our f8 conference, we announced the launch of Timeline as an enhanced and updated version of the Facebook Profile to enable users to better organize and access the growing quantity of their updates, photos, comments, and other content. See Description of Capital Stock. Any representation to the contrary is a criminal offense.
The preliminary prospectus will only be distributed by us and the underwriters named herein and no other person has been authorized by us to use this document to offer or sell any of our securities. We believe that most advertisers are still learning and experimenting with the best ways to leverage Facebook to create more social and valuable ads. We use these cookies to allow you to log-in to your subscriber account. These transactions are considered if they occur with or among willing and unrelated parties. Finally, as more of the economy moves towards higher-quality products that are personalized, we also expect to see the emergence of new services that are social by design to address the large worldwide problems we face in job creation, education and health care.
Some Platform developers may store information provided by our users through apps on the Facebook Platform or websites integrated with Facebook. We cannot be certain that additional financing will be available on reasonable terms when required, or at all. Simplicity In addition to showing you can turn a profit, you will want to keep your prospectus flowing, no matter the length. Stockholders who hold shares of Class B common stock, including our executive officers, employees, and directors and their affiliates, will together hold approximately % of the voting power of our outstanding capital stock following our initial public offering. Enable Developers to Build Great Social Products Using the Facebook Platform. Additionally, if the portfolio companies that are available vary based on benefit options selected, the appendix also would include a separate table identifying the portfolio companies available under each benefit.
We have never declared or paid cash dividends on our capital stock. If the Platform apps that currently generate revenue fail to grow or maintain their users and engagement, if Platform developers do not continue to introduce new apps that attract users and create engagement, if Platform developers reduce their advertising on Facebook, if we fail to maintain good relationships with Platform developers or attract new developers, or if Platform apps outside of social games do not gain popularity and generate significant revenue, our financial performance and ability to grow revenue could be adversely affected. Our quarterly financial results have fluctuated in the past and will fluctuate in the future. As another example, a Facebook user can visit The New York Times website and see which articles have been recommended by friends. As another example, applications on certain mobile devices may automatically contact our servers for regular updates with no user action involved, and this activity may cause our system to count the user associated with such a device as an active user of Facebook. You are writing the prospectus for your specific audience.
You may also contact our office for information about the brokerage firm or stockbroker who sells you securities. For example, in countries such as Chile, Turkey, and Venezuela we estimate that we have penetration rates of greater than 80% of Internet users; in countries such as the United Kingdom and the United States we estimate that we have penetration rates of approximately 60%; in countries such as Brazil, Germany, and India we estimate that we have penetration rates of 44 approximately 20-30%; in countries such as Japan, Russia, and South Korea we estimate that we have penetration rates of less than 15%; and in China, where Facebook access is restricted, we have near 0% penetration. More than four million businesses have Pages on Facebook that they use to have a dialogue with their customers. We have faced, currently face, and will continue to face claims relating to information that is published or made available on Facebook. In that event, the market price of our Class A common stock could decline, and you could lose part or all of your investment. At the end of 2011, we had 3,200 full-time employees, an increase of 50% from the year prior.
This unrecognized compensation expense is expected to be recognized over a weighted-average period of approximately two years. Competition presents an ongoing threat to the success of our business. Through the combination of our mobile sites, smartphone apps, and feature phone products, users can bring Facebook with them on mobile devices wherever they go. If we are unable to expand internationally and manage the complexity of our global operations successfully, our financial results could be adversely affected. Substantial blocks of our total outstanding shares may be sold into the market when lock-up or market standoff periods end.
Our new products and changes to existing products could fail to attract or retain users or generate revenue. Foundations of the Social Web We believe that the web, including the mobile web, is evolving to become more social and personalized. We restrict access to user information to those individuals who reasonably need access to perform their job functions, such as our third party email service, customer service personnel and technical staff. Our previous and future acquisitions may not achieve our goals, and any future acquisitions we complete could be viewed negatively by users, developers, advertisers, or investors. For example, in the fourth quarter of 2010, we significantly increased the number of ads on many Facebook pages.