The stock market's continuing rise to new all-time peaks in recent weeks isn't enticing too many investors to join the party.

The major U.S. exchanges saw trading volume drop to an average of 5.7 billion shares a day last month, the lowest figure for May since 2007, before the 2008-09 financial crisis, according to Credit Suisse Trading Strategy, The Wall Street Journal reports.

The fundamentals aren't strong enough to draw investors to the party, given tepid U.S. economic and earnings growth and expanding price-earnings multiples, according to the paper.

Editor’s Note: Dow Predicted Will Hit 60,000 — Buy These 4 Stocks Now

Investors weren't swayed by the S&P 500's ascent to six record closing highs in May. The index hit yet another peak early Thursday, closing at 1,940.46.

A lack of volatility also has kept investors out of the market. The CBOE Volatility Index (VIX), which measure expectations of volatility for the S&P 500, dropped to a 15-month low Monday.

"There's just not a lot of controversy in the market right now," Scott Migliori, chief investment officer for U.S. equities at Allianz Global Investors, tells The Journal.

Meanwhile, the additional easing announced by the European Central Bank Thursday generated enthusiasm among some U.S. stock investors.

"The stimulus from Europe is a positive thing, especially when you compare it to the fact that the U.S. is starting to ease up," Joe Bell, senior equity analyst at Schaeffer's Investment Research, tells Bloomberg. "Stimulus is being added from a different market."

Editor’s Note: Dow Predicted Will Hit 60,000 — Buy These 4 Stocks Now

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