Please answer a question about the following article about Comcast:

In 2004 and 2007, the American Customer Satisfaction Index (ACSI) survey found that Comcast had the worst customer satisfaction rating of any company or government agency in the country, including the Internal Revenue Service. The ACSI indicates that almost half of all cable customers (regardless of company) have registered complaints, and that cable is the only industry to score below 60 in the ACSI. Comcast's Customer Service Rating by the ACSI surveys indicate that the company's customer service has not improved since the surveys began in 2001. Analysis of the surveys states that "Comcast is one of the lowest scoring companies in ACSI. As its customer satisfaction eroded by 7% over the past year, revenue increased by 12%." The ACSI analysis also addresses this contradiction, stating that "Such pricing power usually comes with some level of monopoly protection and most cable companies have little competition at the local level. This also means that a cable company can do well financially even though its customers are not particularly satisfied."

What organization rated Comcast's customer service the worst in the country in 2004 and 2007?
American Customer Satisfaction Index (ACSI)