The typical American family spends half its income on housing and transportation. That sounds like a sad stat. But it sits atop a happy trend.

Food and clothes consumed 60% of consumer spending in 1900, but as we found more efficient ways to make burgers and socks, that number fell all the way to 17% in 2003. As a result, in most major cities, we spend the majority of our income on planes, trains, automobiles, and dwellings.

But the overall number conceals incredible variety within the country. In small cities or rural areas, housing can be quite cheap. In the Miami metro area, middle-lower-income families spend a whopping 72% of their income on housing and transportation (henceforth: H&T). In Washington, D.C., average monthly H&T costs are the highest in the nation. But as a share of the capital's high income, H&T is, remarkably, the most affordable of any major city.

Here's a graph compiled by the Center for Housing Policy and the Center for Neighborhood Technology of H&T costs as a share of income for families earning between 50% and 100% of the median income in their city. Florida and California lead the pack...

The study (whose 2006-2010 database probably overstates the cost of housing in the Sun Belt) is chock full of fun facts. Here are some that caught my eye.

The Least Affordable Neighborhood in the U.S.? From the report: "In the Philadelphia region, moderate-income households are faced with average housing and transportation costs exceeding 90 percent of their income in some neighborhoods." Wow.

The Price of Density: Housing in Houston isn't so bad -- it's the 8th most affordable large city to own a home in. But the same thing that helps make it an affordable place to own a home (lots of space!) also raises its commuting costs. Factor in transportation, and it's the 8th least affordable large city to live. On the other hand, dense expensive cities like San Francisco, Boston and New York are considerably more affordable when you add in transportation costs because of their superior public transit.

It's Worse for the Poor: For homeowners earning between 50% and 100% of the median income in each city, H&T costs for homeowners who still owe a mortgage average -- average! -- a whopping 72%. Stated differently: Homeowners whose earnings put them in the second quartile of households pay three in every four dollars in mortgage and transportation.

Nationwide, Housing Grew 2X as Fast as Income: Combined H&T expenses average $30,296 for a median-income household, according to the report. But they're growing much faster than median household income.