Roughly 70% of mortgages on the LendingTree network in Nevada are worth less than what is owed on the loan. LendingTree is an online lender exchange and personal finance resource for consumers. According to LendingTree, the average percentage of mortgages in negative equity for each state was 18.1%. The state with the lowest percentage was Oklahoma with 6%. New York was not far behind. There, 6.3% of all mortgages on the LendingTree network were underwater. But Nevada holds the worst at 69.9%. The next closest is Arizona with a negative equity ratio of 51.3%, followed by Florida at 47.8%. From April 2008 to April 2009, home prices in Nevada dropped more than 29%, according to the analytics firm CoreLogic. Nevada also holds the highest foreclosure rate. According to an online foreclosure marketplace, RealtyTrac, one in every 79 homes in Nevada received a foreclosure filing in April. In the first quarter of 2010, foreclosure sales in Las Vegas accounted for 68% of all transactions. Prices in Vegas have fallen so far that regular retail agents have to mark prices down to the REO level.  RealtyTrac finds the average discount on property in some stage in foreclosure compared to a property not in foreclosure sold a 10.5% discount in Vegas through Q110, compared to Los Angeles at 26% and New York City at 28%. Write to Jon Prior.