Arizona foreclosure filings continued to fall in September, down 20.8 percent from September 2011, a real estate data company reported Thursday.

RealtyTrac of Irvine, Calif., said in its monthly report that Arizona was fourth worst in the country, with one foreclosure filing for every 398 housing units. Florida, California and Illinois were worse.

A foreclosure filing is defined as a default notice, a scheduled auction or a bank repossession. One property could represent more than one filing. Arizona recorded 7,148 such filings in September, RealtyTrac reported.

The report showed the lowest foreclosure activity nationally since July 2007.

“We’ve been waiting for the other foreclosure shoe to drop since late 2010, when questionable foreclosure practices slowed activity to a crawl in many areas, but that other shoe is instead being carefully lowered to the floor and therefore making little noise in the housing market — at least at a national level,” said Daren Blomquist, vice president at RealtyTrac.