Question: Which show did the host of the radio program with 6.5 million listeners used to host until 2015 ?

text: List of most-listened-to radio programs
Popular radio shows in the United States
The total listenership for terrestrial radio as of January 2017 was 256 million , [ 3 ] up from 230 million in 2005 . [ 4 ] Sirius XM Radio has a base of 30.6 million subscribers as of 2016 [ update ] . [ 5 ] American Top 40 attracts over 20 million listeners per week . [ 6 ] Rush Limbaugh 's show has been the number one commercial talk show since at least 1987 when record keeping began . [ 1 ] [ 7 ] NPR 's Morning Edition and All Things Considered are the two most popular news programs . [ 8 ] Tom Kent self-estimates his listenership at over 23 million weekly listeners over all of his network 's programs , which span the classic hits , adult hits and hot adult contemporary formats . [ 9 ] Until the development of portable people meters , Arbitron ( Nielsen 's predecessor in the radio measurement business ) did not have the capability to measure individual airings of a program the way Nielsen Ratings can for television , and as such , it only measures in three-month moving averages each month . Portable people meters are currently only available in the largest markets Arbitron serves . Thus , it is impossible under current survey techniques to determine the listenership of an individual event such as the Super Bowl .
In the United States, radio listenership is gauged by Nielsen and others for both commercial radio and public radio. Nielsen and similar services provide estimates by regional market and by standard daypart, but do not compile nationwide information by host. Because there are significant gaps in Nielsen's coverage in rural areas, and because there are only a few markets where the company's proprietary data can be compared against competing ratings tabulators, there is a great deal of estimation and interpolation when attempting to compile a list of the most-listened-to radio programs in the United States. Arbitron, the radio industry's largest audience-measurement company, says that the job of determining number of listeners for Rush Limbaugh is too complicated, expensive and difficult for them to bother with. In contrast, because most UK radio broadcasts are distributed consistently and nationwide, the complications of measuring audiences that are present in American radio are not present for British radio. Talkers Magazine, an American trade publication focusing on talk radio, formerly compiled a list of the most-listened-to commercial long-form talk shows in the United States, based primarily on Nielsen data. In addition to Talkers' independent analyses, radio companies of all formats include estimates of audience in news releases. The nature of news releases allows radio companies to inflate their listener totals by obscuring the difference between listeners at any given time, cumulative listenership over a time frame, and potential audience.
Program Format Network Broadcast Time Weekly listeners ( in millions )
The Rush Limbaugh Show Conservative talk Premiere Midday 15.5
The Sean Hannity Show Conservative talk Premiere PM Drive 15
Marketplace Financial news APM PM Drive 14.8
All Things Considered Newsmagazine NPR PM Drive 14.7
The Dave Ramsey Show Financial talk Self-syndicated Midday 14
Morning Edition Newsmagazine NPR AM Drive 13.1
The Mark Levin Show Conservative talk Westwood One West Coast PM Drive 11
The Glenn Beck Program Conservative talk Premiere East Coast AM Drive 10.5
Coast to Coast AM Paranormal talk Premiere Overnights 10.5
The Mike Gallagher Show Conservative talk Salem East Coast AM Drive 8.5
Delilah Adult contemporary music Premiere Evenings 8.3
The Hugh Hewitt Show Conservative talk Salem East Coast AM Drive 8
BBC World Service Newsmagazine APM Continuous ( 24/7 ) 7.8
The Savage Nation Conservative talk Westwood One East Coast PM Drive 7.5
The Dana Show Conservative talk Radio America Midday 7.25
The Thom Hartmann Program Progressive talk Westwood One Midday 7
The Jim Bohannon Show Talk radio Westwood One Late Night 6.5
Fresh Air Newsmagazine NPR Midday 6
The Joe Pags Show Conservative talk Compass Media Networks East Coast PM Drive 4.5
Wait Wait ... Do n't Tell Me ! Panel game show NPR Weekends 4