The percentage of borrowers 60 or more days behind on their mortgage increased for the sixth straight quarter, hitting a national average high of 3.53 percent in Q2, TransUnion said on Monday. That's up more than nine percent from the previous quarter's reading of 3.23 percent average, and up approximately 51 percent from the same period last year, according to the credit bureau. Mortgage borrower delinquency rates in the second quarter of 2008 were highest in Nevada (6.63 percent) and Florida (6.47 percent), while the lowest mortgage delinquency rates were found in North Dakota (1.10 percent), South Dakota (1.5 percent) and Montana (1.54 percent). On a positive note, six states actually dropped in mortgage delinquency from the previous quarter: Missouri, Kansas, Nebraska, North Dakota, New Hampshire, and Montana. Nebraska dropped the most by 6.67 percent from 1.65 percent to 1.54 percent. The three areas showing the greatest percentage growth in delinquency from the previous quarter were Wyoming (28.3 percent), Oregon (23.5 percent) and Florida (20.2 percent). Surprisingly, given the drop in home prices, TransUnion said that the average national mortgage debt per mortgage borrower rose slightly (0.4 percent) to $192,681, up from the previous quarter's $191,917 total. However, the second quarter 2008 average represents a 3.35 percent increase compared to the second quarter 2007 average of $186,432. Which leads us to ask: with home prices falling sharply, why is mortgage debt increasing? To ponder an answer, it's worth considering that the area with the highest average mortgage debt per borrower during Q2 was California at $361,988, followed by the District of Columbia at $355,875 and Hawaii at $304,096. Quarter to quarter, Montana showed the greatest percent increase in mortgage debt (5.38 percent), followed by Idaho (2.62 percent) and South Dakota (2.38 percent). "The national 60-day mortgage delinquency rate among mortgage borrowers is expected to continue to rise throughout 2008 from a value of 3.53 percent in the second quarter of 2008 to just over 4 percent by year end," said Keith Carson, a senior consultant in TransUnion's financial services group. TransUnion doesn't predict a waning influence for foreclosures until the back half of 2009, Carson said. For more information, visit http://www.transunion.com.