The shadow inventory, that most mysterious of entities, remains a hefty size, according to CoreLogic.

Research firm CoreLogic released its latest residential shadow inventory study yesterday, reporting that the ever-nebulous sector of housing in January 2012 stood at 1.6 million units, or a six months’ supply.

That total is the same as October 2011, but is down from the 1.8 million units in January 2011. CoreLogic said the inventory has been steady in recent months because of an equal flow of supply and demand – just as more units become seriously delinquent and enter the shadow market, distressed transactions of short sales and REOs have offset those additions.

Mark Fleming, CoreLogic’s chief economist, said some segments of the shadow market still have some way to go.

“Almost half of the shadow inventory is not yet in the foreclosure process,” Fleming said. “Shadow inventory also remains concentrated in states impacted by sharp price declines and states with long foreclosure timelines.”

CoreLogic’s system for compiling its data is fairly straightforward. All the firm does is calculate the number of distressed properties not currently listed on multiple listing services that are seriously delinquent, in foreclosure and REO. One sector CoreLogic can not uncover, though, is that of patient home sellers, owners who are holding off on selling their property until home prices recover.

A graph from CoreLogic showing the rise in shadow inventory properties.

Other highlights from the firm’s study included: of the 1.6 million shadow properties, 800,000 were seriously delinquent, 410,000 were in some stage of foreclosure and 400,000 were REO; Florida, California and Illinois account for more than a third of the shadow inventory, and the top six states, which would also include New York, Texas and New Jersey, account for half of the shadow inventory; shadow inventory is at the same level as January 2009, despite three million distressed sales that have occurred in the three years since; and, the highest concentration of shadow inventory is for loans with loan balances between $100,000 and $125,000.

Anand Nallathambi, the president and CEO for CoreLogic, said the next few months will be an important measure for the shadow inventory.

“The shadow inventory remains persistent even though many other metrics of the housing market show signs of improvements,” Nallathambi said. “As we move into what is traditionally the peak selling season for real estate, servicers will certainly be watching closely to see if now is the time to move more inventory out of the shadows.”