#一起读奇虎年报#【产品研发费用6500万美元 营收占比38.7%】In order to attract and retain users, we have invested significant resources in developing security products, cloud-based services, mobile Internet products and other Internet products and services so as to develop and strengthen our products and services and enhance user experience. In 2009, 2010 and 2011, our product development expenses were $10.7 million, $24.5 million and $65.0 million, respectively, representing 33.0%, 42.5% and 38.7% of our revenues in the corresponding periods. We expect our product development expenses to continue to increase as we endeavor to develop attractive products and services that enable users to enjoy a more secure and a higher quality Internet experience.