Two million Californians are living a dream scenario for the American Dream: They own their home free and clear of a mortgage.

New census stats show 29 percent of all owner-occupied residences in the state were mortgage-free last year, up from 23 percent a decade ago. That’s a surprising twist in an era marked by heated discussions about housing affordability as overall ownership numbers slipped.

California’s debt-free flock has grown by 339,000 homes — 20 percent — in a decade. Meanwhile, California homeowners with mortgages have dropped by 498,000 — 20 percent — to 4.93 million since 2006, the peak of an easy-lending era.

Now, 2016’s share of California owners living mortgage-free runs below the U.S. norm: Nationwide, 27.7 million homeowners have no mortgage or 37 percent of all ownership situations. It’s pretty obvious to see that housing costs are a key reason for the gap, as the median value of a California mortgage-less home is $435,000 vs. $166,000 nationwide.

Still, California’s 10-year increase in mortgage-free homes was quite faster than the nation’s 14 percent growth. The growing popularity of mortgage-free living can be tied to numerous factors, including several ugly reminders of painful borrowing mistakes made in last decade’s housing bubble.

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Numerous Californians couldn’t afford their mortgages a decade ago and lost homes to foreclosure — and still don’t own today. Other borrowers today choose to eschew debt as lenders made it more difficult to borrow.

Demographics are in play, too, as an aging and more stable California population stays put and pays off home loans. And years of historically low-interest rates likely motivated some owners to use savings — earning very little at the bank — to pay off a mortgage or buy in all-cash deals.

Mortgage-free living is equally common throughout Southern California counties, with the share of occupied homes having no mortgage relatively the same in all four counties at slightly more than 1-in-4 last year.

Orange County had the region’s fastest growing number of debt-free homeowners: 168,000, up 28 percent since 2006. Those owners lived in homes with a median value of $603,100 in 2016.

Los Angeles County had the most in the area living mortgage-free last year: 405,000, up 17 percent in a decade, in homes worth $520,000.

In Riverside County, there were 130,000 mortgage-free owners, up 22 percent in a decade, in homes valued at $265,600. And in San Bernardino County, 99,000 were mortgage-free — up 21 percent since 2006 — in homes with a median of $257,900.

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California’s mortgage-free crowd must heavily appreciate their lack of house payments as their median household income of $60,000 is well below the $103,000 median income of a mortgaged household statewide.

Census figures show the typical mortgage-free Californian has monthly housing costs of just $546 a month vs. $2,188 for an owner with a mortgage or $1,375 for a renter.

Of course, you need a hefty pile of cash — or lengthy ownership — to own a home free and clear. Fewer Californians are moving, extending their length of ownership and increasing the opportunity to pay off home loans. And post-recession, we’ve seen a significant uptick in all-cash home purchases.

The decline in the number of mortgaged homes isn’t just a California issue: they’re down 9 percent in a decade nationwide.

This pattern should make the housing market a bit more resistant to its own headaches when economic hiccups hit the broader business climate. Of course, one thing fueling the debt-free trend is that tight supplies of homes to buy has made cash buyers a preferred bidder for many sellers.

Don’t forget skittish lenders may have nudged more to pay cash, too. Tight qualification standards, post-debacle, have prevented some financially viable house hunters from buying homes with borrowed funds.

Please note the significant wealth, at least on paper, these mortgage-free owners control. This net worth is an economically significant bounty that can possibly be tapped through loans or sales. Or it may turn into a family nest egg to be passed onto future generations.

My trusty spreadsheet’s rough estimate — multiplying the count of debt-free owners by the median value of mortgage-less homes — shows eye-catching unencumbered home values worth $211 billion in L.A. County; $101 billion in Orange County; and $60 billion in the Inland Empire.

And statewide, by this math, the mortgage-free crowd owns roughly $875 billion of housing — or one-sixth of $5.25 trillion controlled by debt-free owners nationwide.

Note that California’s huge chunk of that national trove comes despite it having last year the fourth-smallest share of mortgage-free ownership nationwide. Only Washington, D.C., Maryland and Colorado, all pricey places to live, ranked lower.

Conversely, it’s little surprise that states with the highest share of mortgage-free owners were in low-cost locales.

For example, West Virginia was No. 1 with 52 percent of its owner-occupied homes mortgage-free. The median value of its mortgage-less homes was $90,000.

Or look at the national home-price disparity this way: In the 11 states with the highest share of owners without mortgages, those properties had estimated combined values of $360 billion … roughly what all of Southern California’s mortgage-less homes are worth.

How much Orange County housing can you buy for $350,000?

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