Nearly three out of four U.S. Internet search users turned to search-engine powerhouse Google (Nasdaq: GOOG) in September.Bottom of Form In a report released Friday, Experian Hitwise said Google accounted for 72.15% of all U.S. online searches for the four weeks ending Oct. 2.

That number represents 1% gain sequentially, Experian Hitwise said.

A distant second was Microsoft's (Nasdaq: MSFT) Bing, garnering 23.64%. Bing-powered search is the result of a 10-year partnership between Microsoft and Yahoo! (Nasdaq: YHOO), but on a standalone basis, Yahoo! Search could muster 13.54%. That's a 5% sequential drop. Bing, meanwhile, gained 2% sequentially to climb to 10.10%.

Description: http:/ remaining 65 search engines, including (2.37%) combined to account for 4.22% of U.S. searches, according to the Hitwise Search Engine Analysis.

Experian Hitwise also said Google is the greatest source of online traffic to key U.S. industries. Google search accounted for 30.03% of the traffic to the travel industry, 22.38% to automotive, 20.10% to shopping, and 16.29% to health.

Google continues to set the benchmark in online search and defines how Internet users browse the Web. Last month, it launched Google Instant, a feature that displays results as a user types and promises to shave off two to three seconds in search time.

However, Bing is an emerging threat. Although small compared with Google, Bing has been growing phenomenally since its launch in June 2009. Last month, it witnessed double-digit sequential growth in searches for health (61%), shopping (55%), automotive (53%), and travel (41%).

Shares of Google closed up 1.20% at $536.35 on Friday. Microsoft shares closed up 0.16% at $24.57, and Yahoo! closed up 1.83% at $14.49.

International Business Times, the Global Business News Leader

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Google and Microsoft are Motley Fool Inside Value picks. Google is a Motley Fool Rule Breakers choice. Motley Fool Options has recommended a diagonal call position on Microsoft. The Fool owns shares of Google and Microsoft. Try any of our Foolish newsletter services free for 30 days. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community. This article has been lightly edited. The Motley Fool has a disclosure policy.