How common is pansexuality?

Google search trends show that interest in pansexuality is at an all-time high. Surveys show very low percentages of general populations reporting to be pansexual, but many people who actually identify as pansexual will publicly identify as bisexual or queer to avoid having to explain or defend their self-identification. Additionally, statistics often group them in with other sexual orientation groups such as bisexual or polysexual. Pansexuality has a significant online presence, more stereotypically associated with the site Tumblr where a large number of people who identify as pansexual first chose to come out and discuss their sexual orientation.