But the momentum effect is huge.
Might that momentum effect work for the overall stock market?
"But it has a momentum effect as we keep going on to the next several states".
There is also a momentum effect in M&A, especially as the cycle turns.
Clearly the momentum effect cannot last for ever or share prices would head for infinity.
The investment-management industry may become even more commoditised.The momentum effect raises a further important issue.
Professor Heston says it is important not to confuse the monthly patterns with what Wall Street calls the momentum effect.
Longer-term studies have confirmed that this "momentum" effect has been observable for much of the past century.
A fourth is to use the "momentum effect" to buy stocks that have recently risen in price.
Similarly bad years were 1975, 2000 and 2003.The momentum effect allows investors to get rich slowly.
"I think there will be a momentum effect," said LeRoy Walters, a bioethicist at Georgetown University who met with Mr. Bush and his advisers last week.
