NEW YORK (

TheStreet

) -- "Stock split" is a popular search topic after

Citigroup

(C) - Get Report

began trading post-split on Monday, reflecting its completion of a 1-for-10 reverse stock split on Friday.

The change reduces Citigroup's outstanding share count by tenfold, and is expected to have a significant impact on volume in the stock, which has consistently been the most active issue on the New York Stock Exchange since plunging into single digits during the financial crisis.

The move was designed to let more large investors, such as pension and mutual funds, buy Citigroup stock, as many large funds are not allowed to own stocks that trade under $5.

Citi's stock closed Friday at $4.52. Shares opened at $44.89 on Monday and were dropping 2.5% in mid-afternoon trading to $44.08.

"Giro d'Italia" is a heavily search topic after Belgian cyclist Wouter Weylandt died Monday following a high-speed downhill crash at the cycling race in northern Italy.

Weylandt, 26, fell more than 12 miles from the finish line. Paramedics rushed to the scene but were unable to resuscitate him.

"He was unconscious with a fracture of the skull base and facial damage," Giro doctor Giovanni Tredici said. "After 40 minutes of cardiac massage we had to suspend the resuscitation because there was nothing more we could do."

"Mississippi River" is a trending search topic as authorities urge residents along the river's banks from Arkansas to Tennessee to evacuate.

The river is expected to rise to historic levels this week as another round of storms move into the region. On Saturday, water levels around Memphis rose to 47.6 feet, said National Weather Service spokesman Richard Okulski.

River levels could reach as high as 48 feet outside the western Tennessee city as soon as Monday, a day earlier than originally forecast. That level would still be short of a 1937 record of 48.7 feet, which led to more than 500 deaths and the flooding of roughly 20 million acres.

"Gas prices" is a hot Internet search as the price at the pump started to drop after reaching record highs across the nation last week.

The average gas price in the United States spiked to nearly $4 last week, according to

GasBuddy.com

, but the cost has since dropped a few cents to an average just under $3.94.

Some industry analysts expect fuel prices to continue to dip further in the next few weeks as the summer driving season begins and more gas becomes available.

The chatter on Main Street (a.k.a. Google, Yahoo! and other search sites) is always of interest to investors on Wall Street. Thus, each day, TheStreet compiles the stories that are trending on the Web, and highlights the news that could make stocks move.

--

Written by Theresa McCabe in Boston

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