As the equities market marches toward new highs, investors have been trimming their U.S. stock exchange traded fund exposure.

For instance, over the past week, the SPDR S&P 500 ETF (NYSEArca: SPY) has lost $639.2 million in assets, according to

According to Bank of America Merrill Lynch, global investors have been cutting their U.S. stock exposure this month, with appetite for U.S. stocks tumbling to their lowest level since January 2008, as the decline in confidence for corporate profits caused fund managers to trim equity holdings to underweight, reports Jenny Cosgrave for CNBC.

In a recent Bank of America Merrill Lynch survey, 19% of investors polled last week were running underweight positions, compared to the heavy overweight stance held in the first quarter of the year.

The greater underweight positions suggest that investors are growing cautious over the continued strength in U.S. equities after the S&P 500 and Dow Jones Industrial Average closed at record highs.

“There is no loss of faith in economic recovery, and positioning still assumes that the U.S. dollar goes up, but doubts are creeping in – hence this jump in allocation to cash,” Michael Hartnett, chief investment strategist at BofA Merrill Lynch Global Research, said in a note.