Continuing from previous search stats from Hitwise, Compete, and comScore, Nielsen Online is now out (PDF file) with search engine share figures in the United States for March 2008. Similar to Hitwise and comScore, Google remains at a high but unlike some of the others, Microsoft and Yahoo come off lows.

Searches that happened on the five top search engines in the pie chart above:

• Google: 58.7%
• Yahoo: 18.1%
• Microsoft: 12.0%
• AOL: 4.1%
• Ask: 2.4%

Note that in the chart above, traffic from Ask.com-owned My Web Search is not combined by Nielsen with the Ask figure. If it were, the Ask figure would rise to 3.3 percent.

The trend over time? Here’s data going back to November 2007 (data from previous periods doesn’t compare because Nielsen changed its methodology):

Google matched the high it set in the previous month, hitting 58.7% once again. Yahoo had a high of 19% in January, then dipped to 17.6% the next month, but for March, it came up to the 18.1% mark. Microsoft hit its lowest point over the period in February, 11.2%, but then came up to 12% in March.

How about number of searches versus market share?

• Google: 4.8 billion
• Yahoo: 1.5 billion
• Microsoft: 1 billion
• AOL: 334 million
• Ask: 200 million

The trend:

As you can see, while Google maintained the same overall share, in terms of actual number of searches, it had a large rise. Yahoo and Microsoft also saw gains.

Caveat Time!

As a reminder, my general rules when evaluating popularity stats:

• Avoid drawing conclusions based on month-to-month comparisons. Lots of things can cause one month’s figures to be incomparable to another month. It’s better to see the trend across multiple months in a row.
   
• Avoid drawing conclusions based on one ratings service’s figures. Each service has a unique methodology used to create popularity estimates. This means that ratings will rarely be the same between services. However, a trend that you see reflected across two or more services may give you faith in trusting that trend.
   
• Consider Actual Number Of Searches: While share for a particular search engine might drop, the raw number of searches might still be going up (and thus they might be earning more money, despite a share drop). This is because the "pie" of searches keeps growing, so even a smaller slice of the pie might be more than a bigger slice in the past.

Related Topics: Stats: NetRatings | Stats: Popularity

---

About The Author: Danny Sullivan is editor-in-chief of Search Engine Land. He’s a widely cited authority on search engines and search marketing issues who has covered the space since 1996. Danny also oversees Search Engine Land’s SMX: Search Marketing Expo conference series. He maintains a personal blog called Daggle (and maintains his disclosures page there). He can be found on Facebook, Google + and microblogs on Twitter as @dannysullivan. See more articles by Danny Sullivan

---