WASHINGTON, D.C. --- An independent study of oil markets concludes that speculation by large investors -- not supply and demand -- was a primary reason for the surge in oil prices during the first half of this year and for the subsequent price declines, the Associated Press reported.

Conducted by Masters Capital Management, the study concluded that investors poured $60 billion into oil futures markets during the first five months of the year as oil prices soared from $95 a barrel in January to $145 a barrel by July.

Michael Masters of Masters Capital Management said: "We have clear evidence the fund flow pushed prices up and the fund flow pushed prices down." He called the amount of money moving into oil futures markets by large institutional investors in the early part of the year "way off the scale."

Further, Masters said, the study showed that investors "began a massive stampede for the exits" July 15, sparking a price decline.