After winning the World Series on Monday in a five-game series over the Texas Rangers, the San Francisco Giants were treated to a ticker-tape parade with a turnout of more than one million on Wednesday.

Equity analysts say Giants fans and others may have more to cheer about if certain historical market trends prove true this year.

League Tables

According to S&P Capital IQ data, the World Series win by the Giants – members of the National League – means the markets are poised to do better in 2011 than they would with a Rangers victory.

Based on the 30 series won by a National League team, the average S&P 500 return was 15% for the year following a National League victory vs. an average of 9% for the 43 years that followed a series won by the American League.

In fourth quarter, when a National League team won, the average gain was 4.2%. The markets rose an average of 6.2% in up years and declined 10.2% on average in down years.

When an American team won, the fourth-quarter saw an average overall return of 2.8%, with gains of just 0.1% when the markets were up and losses of 10.4% when the markets were down.

“There have been more years with American League teams losing,” said Richard Peterson, a director of S&P Capital IQ, which appears to be a good thing for the markets.

Series Length

Historically, a five-game series has seen average market returns of 17% for the year following the World Series but just 1.8% for the fourth quarter.

When the series ended in the fifth game and a National League team won, the average gain was only 0.6%, Peterson says.

“Hopefully we will go against this tradition,” Peterson said in a phone interview Friday.

In years with six-game World Series, the average returns were 15% for the next year, and the returns fell to 8% for the year following a seven-game series.

Sweeps, or four-game series, return the lowest average performance, with returns of 7% the next year.

S&P Capital IQ looks at data since 1926, though the baseball championships have been held since 1903.

Giants History

In 1954, when the New York Giants swept the Cleveland Indians, the S&P 500 moved up 12.6% in the fourth quarter.

“I hope we will see that again!” Peterson shared.

And, when the equity analyst reviewed what happens for a second consecutive championship things look even better. “The New York Yankees had a repeat in 1928, and in the fourth quarter that year, the S&P was up 15.4%.”

That’s a fact that’s music to the ears of Giants fans, at least.

“This year’s been a lot of fun, but a bit of a disappointment for baseball fans on the East Coast,” said Peterson. “There’s always next year.”

Political Notes

From a political stand point, Peterson says, it’s worth noting that in 1954, the last time the Giants won the World Series, there were also mid-term elections, and a write-in candidate for the U.S. Senate won.

This bodes well for Alaska’s write-in Senatorial candidate Lisa Murkowski. “There could be a parallel there,” Peterson said, “though I like to stick to looking at baseball’s relationship with the market.”