1.) There are many people and organizations that would be interested in this statistic. However, consumers who drive cars would be the most interested in the changes in gasoline prices, as they have to purchase gas in order to drive their vehicles.
2.) According to this websites, the U.S. Energy Information Association collects these prices and statistics on a weekly basis.
3.) The average U.S. gas prices is $3.089 per gallon. This prices has risen $0.019 from last week, and $0.338. Gas prices have been rising slowly over the past year. As a related statistic, diesel prices have risen $0.002 per gallon from last week (currently $3.333) and $0.454 from last year.
U.S. Energy Information Association. EIA, - 2011. Web. 10 Jan. 2011.