Kayak.com launched a "Best Fare Trend" graph that offers historical airfare data allowing users to track and identify the cheapest airfares found within the past 90 days on Kayak.com.

The new graph joins two other innovative tools recently launched on Kayak.com, Kayak Buzz and Best Fare History, all of which empower users with the ability to compare historical data for prices and itineraries over a specific time period, enabling a more informed purchasing decision.

"Airfares can change thousands of times a day so consumers are confused about when to purchase," said Steve Hafner, Kayak.com CEO and co-founder. "Kayak.com's Best Fare Trend graph displays price fluctuations for a specific route on a single departure date or over various dates so travelers can always be confident that they found the lowest fare. With the launch of Best Fare Trend, Kayak.com now offers more historical airfare data tools than any other travel site."

Best Fare Trend charts pricing for city/date pairs found by Kayak.com users over the past 90 days. The chart is available for searches that have been queried five or more times. Currently, there are Trend graphs for 415,000 city pair/date combinations, covering the most heavily traveled markets. The city pair with the most diverse set of dates is currently Newark to San Juan, Puerto Rico with over 251 departure dates searched.

The Best Fare Trend graph appears at the top left hand corner of the flight results page. For detailed trend information, consumers click on the "details" link above the chart. A new window opens with a larger graph and Best Fare History list. Consumers can use the date drop down menu to change the departure date and instantly review a new Trend graph. For the lowest fare, users should choose "any day" which charts two data points: "average low fare found" and the "absolute best fare found" for an entire month.

Kayak.com was the first travel site to provide historical data to consumers with the November 2005 launch of Kayak Buzz, a tool that displays the lowest fares to the 25 most popular destinations from any airport or city. In May, Kayak.com enhanced the Buzz product with Best Fare History, an option to view up to 100 fare/itinerary combinations for a specific city pair found by other Kayak users over the past 36 hours. A "check availability" link is integrated with all three tools, allowing the consumer to check instantly for real-time availability and pricing.