How long has Prosper existed?

I'm curious to know, how long has Prosper been operating in the financial marketplace? It's a platform that connects borrowers and lenders, offering a unique way to access credit and invest funds. So, has it been around for a few years, or is it a more recent entrant in the world of peer-to-peer lending? Understanding its longevity can help potential users assess its stability and reliability in the industry.