(Bloomberg) -- Investors’ appetite for U.S. equity exchange-traded funds has weakened to levels not seen in four years as demand for safety drove more money to fixed income.

The CHART OF THE DAY shows that ETFs buying stocks have received fewer deposits than bond ETFs for a second straight quarter, with the gap reaching more than $13 billion, poised for the worst six-month period since June 2010. That’s a shift from 2013, when stocks attracted 13 times more money.

Demand for equities is slowing as small-cap and Internet shares tumbled this year amid concern about rising valuations and a first-quarter economic contraction. While growing unrest from Ukraine to Iraq helped drive investor preference for fixed income, improving growth from housing and employment will sustain the bull market in stocks and stoke inflation, making bonds less attractive, according to George Young, a partner at St. Denis J. Villere & Co. in New Orleans.

“A lot of people remember 2008 and they remember their stock portfolios dropping drastically in such an unexplainable manner,” Young, who helps oversee about $3 billion, said in a June 16 phone interview. “They say, ‘I’m going to make this assumption that the economy doesn’t get over-heated and I’m going to make this assumption that stability is what I need for the longer term.’ But I think they drastically under-estimate the power of inflation.”

The Standard & Poor’s 500 Index is up about 5% this year, overcoming a selloff that started with small-cap and Internet losses and drove the benchmark measure to a two-month low in April. The Bloomberg US Treasury Bond Index has returned 2.8% this year as yields on Treasury 10-year notes fell to an 11-month low in May.

U.S. equity ETFs have attracted $11.8 billion this year, less than half the $25.2 billion deposits that went to bonds, data compiled by Bloomberg show. In 2013, almost $140 billion flooded to stocks, compared with $10 billion inflows for fixed income.

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