According to a new report intended for client use by real estate investment bank Eastdil Secured, office building capital flows here dropped a heart-pounding 87 percent in the first six months of the year compared to last year. That's much bigger than in any other major metropolitan area studied and left Chicago 20th out of 25 cities in terms of the dollar amount invested here.

Similar research comes from RCA/CBRE. It projects that in terms of all commercial transactions (not just office), Chicago still will rank fifth in the country for investment in the second half of the year, but it reports the dollar total is slipping, down 57 percent in the first half. A third source, Real Capital Analytics, has it down 32 percent over six months and 10.8 percent over the last year, compared to a 13.7 percent gain for North America as a whole in that year.

One more data dump: Consultancy PricewaterhouseCoopers and the Urban Land Institute produce an annual survey of emerging trends in real estate in the U.S. and Canada. As reported by my colleague Alby Gallun, the 2019 report ranked Chicago 49th of 79 cities in terms of potential asset growth. That's down from 42nd a year ago and 19th two years ago—not a good trend.

So what should we make of this as Lightfoot prepares a list of new taxes, some populist aldermen urge new or higher taxes on office leases, vacancies, employees and sales, and newly installed Cook County Assessor Fritz Kaegi continues to move to shift a higher share of the property tax load to business classifications?

"There's a lot of companies that want to be here. But you can't pick up a newspaper and not see bad news" about underfunded pensions, Lightfoot's budget hole and the like, says one top industry official who reports investors are being "scared off." Adds another, "It's the uncertainty of Lori and Fritz together. Once you turn the (capital) spigot off, it's off."

Team Lightfoot sees it differently.

"There's lots of other reports that show healthy growth," says Deputy Mayor Samir Mayekar, noting recent new projects in the Fulton Market area and Uber's decision to lease 450,000 square feet of space in the Old Post Office. "I'm on the phone every day with companies that are looking to expand here."

Others hold more of a middle view, emphasizing among other things that investors nationally are more skittish than they were before President Donald Trump kicked off a trade war with China.

"We've always come out of these changes in capital flows," says Jon DeVries, former head of Roosevelt University's Bennett Institute of Real Estate. What counts is core demand for space, and Chicago still benefits from its location in the heart of America and the recent trend by companies to relocate downtown, he says.

"It remains to be seen" just how serious the recent shift in capital flows is, says Rachel Weber, professor of urban planning and policy at the University of Illinois at Chicago and author of "From Boom to Bubble: How Finance Built the New Chicago." She's not ready to decide, but adds that given where we are in the real estate cycle, it's fair to ask, "Are we kicking them when they're down?"

I don't know the answer. My advice: Be careful, Mayor—very careful. Nearly 600,000 people work in Chicago's central area, and, believe me, they need their jobs.