Early chairmen of C-SPAN include Bob Rosencrans, John Saeman, Ed Allen and Gene Schneider. C-SPAN does not sell commercials or solicit donations on air; instead, it receives nearly all of its funding from subscriber fees charged to cable and direct-broadcast satellite (DBS) operators. , C-SPAN received 6¢ of each subscriber's cable bill for an annual budget of $60 million. As the network is an independent entity, neither the cable industry nor Congress controls the content of its programming.  , the network has 282 employees. C-SPAN is led by co-CEOs Rob Kennedy and Susan Swain. Founder and former CEO Brian Lamb serves as the executive chairman of the board of directors. The majority of C-SPAN's employees are based at C-SPAN's headquarters located on Capitol Hill in Washington, D.C., however in 2003 television studios were opened in New York City and Denver, Colorado. These studios use digital equipment that can be controlled from Washington. C-SPAN also maintains archives in West Lafayette, Indiana at the Purdue Research Park under the direction of Dr. Robert X. Browning. The C-SPAN networks are available in more than 100 million households , not including access to the C-SPAN websites. More than 7,000 telephone callers have participated with discussion on "Washington Journal" . There are no official viewing statistics for C-SPAN because the network, which has no commercials or underwriting advertisements, does not use the Nielsen ratings. However, there have been a number of surveys providing estimates:  A 2009 C-SPAN survey of viewers found that the network's most-valued attribute was its balanced programming. The survey's respondents were a mixed group, with 31% describing themselves as "liberal," while 28% described themselves as "conservative", and the survey found that C-SPAN viewers are an equal mixture of men and women of all age groups. C-SPAN's public service nature has been praised as an enduring contribution to national knowledge. In 1987, Andrew Rosenthal wrote for "The New York Times" about C-SPAN's influence in political elections, arguing that C-SPAN's "blanket coverage" had expanded television journalism "into areas once shielded from general view". The network has received positive media coverage for providing public access to proceedings such as the Goldman Sachs Senate hearings, and the U.S. 2010 Healthcare Summit, while its everyday programming has been credited with providing the media and the general public with an intimate knowledge of U.S. political proceedings and people.