Foreclosure levels skyrocketed to 90 percent above year-ago levels, according to the most recent report from RealtyTrac, release late yesterday. Foreclosures were also up 19 percent versus last month, according to Realty Trac, signaling that the worst of the U.S. housing slump may not yet be over.

Nevada, Colorado, California post top foreclosure rates Nevada registered a May foreclosure rate of one foreclosure filing for every 166 households — the nation’s highest for the fifth month in a row and nearly four times the national average. The state reported a total of 5,235 foreclosure filings during the month, a 40 percent increase from the previous month and nearly five times the number reported in May 2006. Colorado documented the nation’s second highest state foreclosure rate, one foreclosure filing for every 290 households — 2.3 times the national average. The state reported 6,321 foreclosure filings, a nearly 9 percent increase from the previous month and an increase of more than 50 percent from May 2006. The state’s foreclosure total was eighth highest among the states. California foreclosure activity increased 30 percent from the previous month and more than 350 percent from May 2006, boosting the state’s foreclosure rate to third highest in the country. California documented one foreclosure filing for every 308 households, more than twice the national average. Other states with foreclosure rates ranking among the nation’s 10 highest in May were Florida, Ohio, Arizona, Georgia, Michigan, Indiana and Connecticut. California, Florida, Ohio document largest foreclosure totals For the fifth straight month California reported the most foreclosure filings of any state, with 39,659 in May. Florida reported 21,704 foreclosure filings, the second biggest state total. Foreclosure activity in Florida increased 52 percent from the previous month and 144 percent from May 2006, raising its foreclosure rate to one foreclosure filing for every 336 households — fourth highest among all the states. With 13,214 foreclosure filings reported in May, Ohio documented the nation’s third highest state total for the third month in a row. The state’s foreclosure activity increased 16 percent from the previous month and more than 150 percent from May 2006, resulting in a foreclosure rate of one foreclosure filing for every 362 households — fifth highest among the states and 1.8 times the national average. Other states with foreclosure filing totals among the nation’s 10 highest in May were Texas, Michigan, Georgia, Illinois, Colorado, Arizona and Nevada.

Be sure to read the full press release for state-by-state statistics.