(CBSNews) -- Taken a trip to the emergency room lately? Moved across country for a new job? If you're like millions of Americans, the unexpected medical costs or security deposit for your new pad blew a hole in your budget.

That's the upshot of a new Bankrate survey that found six of 10 people in the U.S. lack the savings to handle an unforeseen $1,000 expense, highlighting just how close to the financial edge even those with a job often find themselves.

"You have a gap with what people are making and what they can afford," said Scott Astrada, director of federal advocacy at the Center for Responsible Lending.

A range of factors account for the dearth of savings, including weak wage growth going back decades, volatility in worker pay, and the rising cost of things like housing, education and health care.

"All this has combined to form a perfect storm to leave millions of Americans high and dry when it comes to financial stability," Astrada said.

The findings square with other data pointing to widespread economic insecurity in the U.S. — even with unemployment at its lowest rate in nearly 50 years. Four in 10 Americans struggle to pay for groceries, housing and other basic needs, concluded a 2018 study by the Urban Institute, a centrist think tank.

For households, that can result in a genuine financial crisis when the median emergency expense runs $3,750, according to Bankrate, which surveyed 1,005 respondents by telephone in the first week of January.

Ever shrinking savings

The amount of money people stash away has been declining for decades, noted Greg McBride, CFA and chief financial analyst at Bankrate.com. In the 1970s, Americans saved just over 12 percent of their income, according to the Bureau of Economic Analysis. By 2017 (the latest year for which data are available), that figure had shrunk to 6.7 percent, and even that represents an improvement over the paltry savings rate in the previous decade when two recessions crushed individual balance sheets.

In 2018, despite rising wages and strong job creation, only 40 percent of respondents to the Bankrate survey said they were able to cover $1,000 unplanned expenses.

Millennials typically face higher sudden expenses — exceeding $2,500 — than either baby boomers or Gen-Xers. As they enter the workforce, younger adults are more likely to switch homes, which usually requires putting down a security deposit, and often pay out of pocket for health care costs.

Healthy habits

Still, Americans of all ages can find themselves caught short, McBride said. "Unplanned expenses can happen to anyone at any time, it's not a compunction of a particular factor, so we don't see a very big disparity between age groups."

Faced with an emergency expense, younger boomers were most likely to tap their savings, while their older peers tended to pay with a credit card. Millennials and Gen-Xers were most likely to borrow from family members or friends.

So how much savings should you have for those unexpected bumps in the road? McBride recommends saving a minimum of six months' worth of expenses — more if you're the sole breadwinner. The key is automating as much of the process as possible using payroll deductions for your workplace retirement plan, setting up a direct deposit into a dedicated account for emergency expenses and searching for online savings accounts with competitive returns.

"The biggest barrier of saving is not being in the habit of saving. And establishing the habit of saving means prioritizing saving first and spending second," McBride said.