Prosper.com, a California-based peer to peer lending company, has seen a 125% increase in the dollar value of loans that the company has setup during the last six months.

During the month of March, Prosper setup $4,513,931 in loans between borrowers and lenders on its website. Comparatively, Prosper.com setup a mere $2,007,958 in loans during the month of September 2010. The company has seen steady growth in loan originations, with $2.5 million in loans in October 2010, $2.65 million in loans in November 2010, $3.2 million in loans in December 2010, $3.3 million in loans in January 2011 and $3.65 million in loans in in February 2011. As of April 19th, Prosper.com has originated $2.48 million in loans for the month.

An extrapolation of this data might suggest that Prosper.com will see about $3.9-$4.1 million in loans during the month of April. The final amount of originated loans for the month of April may be larger than the projected total given that the company tends to setup more loans during the final week of any given month.

Although the company has seen significant growth in the number of loans it has arranged during the last 24 months, it has not yet been able to reach the monthly loan origination numbers that it was generating before the SEC filed a cease and desist letter against the company in November of 2008 for selling unregistered securities. The company did get its legal issues ironed out and resumed issuing loans in the middle of 2009, but had since struggled to consistently generate the same volume of loans that it did in 2007 and 2008.

Prosper.com has had a number of special promotions during the last several months to help boost its loan origination numbers. To celebrate its fifth anniversary, Prosper.com had a promotion in which they would pay the second payment for borrowers that registered for loans on certain dates. Prosper.com also offered a number of bonuses to lenders that funded additional loans through their service.

Despite Prosper.com’s recent growth, Lending Club remains the 800 pound gorilla in the U.S. peer to peer lending industry. During the last year, Lending Club has been consistently arranged more than $10 million in loans on a monthly basis. Lending Club has originated a total of $257,195,025 as of April 19th, 2011 and paid $20,614,341 in interest to investors on its website.