This is what Americans are willing to sacrifice 20% of their salary for

Alli, UC-Davis student and JoyRun driver.

The security that comes from getting a set amount of money on a regular schedule is so attractive to Americans that they are willing to sacrifice up to 20 percent of their salary for it. And yet that stability is as elusive as it is alluring.

A national average of 55 percent of Americans experience serious income fluctuations month to month, according to new research from JP Morgan Chase & Co., meaning that what workers bring in can vary by over 30 percent. And, their experts report, "the typical household" isn't set up to "weather this volatility."

That's stressful, since not knowing how much money you're going to earn in any particular pay period makes it hard to budget. Yet given the vagaries of the gig economy and the fact that even some corporate employers make a habit of tweaking or announcing schedules at the last minute, it can be hard to know how much you're actually going to be able to bring in.

No wonder so many Americans are living paycheck-to-paycheck.

Young people and lower-income workers are particularly vulnerable, since 70 and 74 percent of them, respectively, are forced to cope with this kind of income volatility. The New York Times reports that "virtually every major retail and restaurant chain" puts their workers through some version of this, since tech advances make it possible and also because "managers are often compensated based on the efficiency of their staffing."

But almost all Americans are affected, JP Morgan reports, noting that "the decline in real wages since 2009 for all income groups except the top 5th percentile means that life is harder to afford in general, but even more so when earnings dip below average."

According to their findings, "median income individuals experienced nearly $500 in labor income fluctuations across months, with spikes in earnings larger but less frequent than dips."

Transitioning from one job to another, as four out of ten of those surveyed did in a year, leads to shifts in pay, but even a seemingly stable job is often at fault: "Most of the month-to-month volatility in take-home pay (86 percent) came from variation in pay within distinct jobs."

The New York Times concurs, reporting that "a new wave of research shows that the main culprit is not the so-called gig economy, but shifting pay within the same job," and adding that "turbulence has replaced the traditional American narrative of steady financial progress over a lifetime."

As a result, according to the Times, "stability is worth a lot to workers. On average, employees are willing to give up a fifth of their weekly wage to avoid a schedule set by an employer on a week's notice."

Experts encourage everyone to keep three-to-six months' worth of expenses in an emergency fund to cope with an accident, crisis or layoff, and former CNBC host Suze Orman suggests you aim to put away enough to support yourself for about a year. Unfortunately, most Americans aren't able to meet that goal: The majority of them have under $1,000 saved, total. Half of all workers in the U.S. have nothing put away for retirement.

To help create that kind of buffer for yourself, JP Morgan suggests that "key, predictable savings opportunities include December to March pay spikes, five-Friday months for individuals with jobs that pay every two weeks or weekly, and tax season for those who receive tax refunds." Those are all good chances to squirrel away extra cash.

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