It's no secret that income inequality has widened dramatically in the last 30 years. Between 1979 and 2005, the top five percent of American families saw their real incomes increase 81 percent while the lowest-income fifth saw their real incomes decline by one percent:

The gap is often most stark in urban areas. Chicagoland's middle class population -- defined as those who earn between 80 percent and 150 percent of their metro area’s median income -- declined by 14 percent between 1970 and 2005. The top 10 percent of employees now earn 6.3 times more than the bottom 10 percent of the city’s workforce.

The take-away: Chicago's once-vibrant middle class is slowly vanishing.

New York City is experiencing the same phenomenon, where economic development policies designed to foster unbridled growth have modernized parts of the city but also contributed to intense levels of inequality. Activists there want to even the playing field. After four years of collaboration, a coalition of civic leaders, neighborhood advocates,  unions, local development corporations, and environmentalists published the Blueprint for Economic Development (PDF), a platform of 64 policy ideas that they believe will improve economic opportunity, environmental sustainability, and the quality of life in the Big Apple.

Fortunately, most of these proposals aren't location-specific. While Chicago already addresses some of the provisions listed, city officials would be wise to page through the book and see what a comprehensive platform for shared economic growth actually looks like.

Here are a few of those ideas, along with our analysis of how they could be applied to Chicago:

Adopt a city minimum wage
Cities across the country -- Washington D.C., San Francisco, Philadelphia -- have implemented living wage bills to compensate employees who live and work in expensive locations without suffering catastrophic busines losses. Such a move would also partially solve the ongoing dispute over the wages paid by big box chains such as Wal-Mart.

Continue to support and expand the portfolio of affordable housing
The need to preserve and expand housing stock is urgent and the city is dragging it's feet. More pressure is needed to ensure that safe, affordable shelter is available to every Chicagoan.

Bring grocery stores with living wage jobs to underserved neighborhoods
Using its planning process, incentive programs, and land use tools, there's no reason Chicago can't lure grocers into the city's food deserts. And again, if the businesses pay a living wage, the jobs will be valuable to -- rather than exploitative of -- the members of those communities.

Support transportation improvements for lower-income neighborhoods
While fixing up stations in the Loop has its value, improving the mobility for lower-income households and outlying neighborhoods is a cost-effective and environmentally smart way to promote economic growth.

There are tons of other great concepts in the report, so be sure to check out the whole thing.