A new study by the Brookings Institute highlights many of the perceived changes to San Francisco's economic landscape since the Great Recession, including the fact that out of all the nation's cities, we experienced the biggest jump in incomes for our richest households between 2007 and 2012. So, in case you needed proof that the tech-wealthy and others in the Bay Area were basically immune to the recession, here it is.

But San Francisco simultaneously saw the greatest widening of the gap between upper-end incomes and its lowest incomes, with the city's poorest households seeing annual incomes drop by about $4,000 over the same period. Joining S.F. in being the cities with the biggest gaps between rich and poor are Boston, Atlanta, and Miami, but the study points out that the reasons for similar ratios are different for each city, with San Francisco having the highest average income overall among high-earner households, at $354,000, while Miami has a similar degree of economic inequality because of its sheer number of poor neighborhoods where incomes top out around $10,000.

The study, titled "All Cities Are Not Created Equal," points out several things that should come as no surprise, including the fact that economic inequality is greatest in our nation's largest and most vibrant cities, with New York (with a population 10 times that of San Francisco) coming in 6th place in terms of the gap between rich and poor. There, Mayor Bill DeBlasio has vowed to take on this inequality, but it remains to be seen how well a mayor can address a problem that has its roots in economic success and the desire of more affluent people to live in vibrant urban areas. The poor increasingly live in suburbs in this country, and cities where the income gap is lowest tend to be places where many of the neighborhoods are, basically, suburban — like San Jose, for instance, which ranks 36th on this list.

But in conclusion, it's not just artists and old people getting evicted that we need to worry about:

A city where the rich are very rich, and the poor very poor, is likely to face many difficulties. It may struggle to maintain mixed-income school environments that produce better outcomes for low-income kids. It may have too narrow a tax base from which to sustainably raise the revenues necessary for essential city services. And it may fail to produce housing and neighborhoods accessible to middle-class workers and families, so that those who move up or down the income ladder ultimately have no choice but to move out.

Yeah, and sadly, Oakland's not far down the list either, ranking in 7th place, just below New York, for its income gap. Vallejo, anyone?