Classic AT40 with Casey Kasem: July 4, 1970 through August 6, 1988
"American Top 40" debuted the weekend of July 4, 1970. The concept of playing the 40 most popular songs from a national chart was a new one, and no one was sure of the success of the show at the time. Listeners first heard Casey Kasem count 'em down on station KDEO in El Cajon/San Diego, California at 7 pm on Friday, July 3, 1970. KDEO was one of just a few stations across the USA to air the show on its first weekend.
During AT40's first year, the show was sent to radio stations on reel-to-reel tapes. After the first year, AT40 was recorded on vinyl. One side of a 33 1/3 rpm LP could hold a half hours worth of show. Thus, 4 records would be needed for each 4 hour show. On the records, there would be the show and promos for the show. Initially, commericals were included with the show, but this quickly changed to no commercials included. Commercials would return in 1982 when the company that produced AT40 (Watermark) was bought by ABC networks. The records would be placed in a box or record sleeve and mailed to a radio station. Each station received its own copy of the show. After the show was aired, the items were to be destroyed. Luckily, many radio personnel did not destroy the copies, and many exist for the collector today.
Throughout the 1970s, and into the 1980s the show's popularity increased. One of the ways this happened was that the owners of the show would send "demo reels" to radio stations to get them to sign on to the show. By the early 1980s the show was heard on over 500 radio stations in the USA alone.
Casey counted down the 40 biggest hits off of Billboard's Hot 100 Singles chart. Originally a 3 hour program, AT40 expanded to 4 hour length in 1978. Besides the top 40, AT40 played Long Distance Dedications and extras. The first Long Distance Dedication, "Desiree" by Neil Diamond, aired in August 1978. Fans could also write in questions and have the AT40 staff answer them, sometimes on the air. These were known as "Question Letters".
In the spring of 1979, AT40 published its first book, "Casey Kasem's Top 40 Yearbook". This book covered every song that hit the Top 40 from late 1977 to late 1978. Also included in the book were biographies and pictures of the artists who charted. Today the book is a collectible since another yearbook was never produced.
Special countdowns aired occasionally through the 1970s and 80s. Year-end countdowns, Christmas countdowns, and AT40 Book of Record shows are just a few of the many popular specials aired.
Trouble for AT40 began in 1988. Due to contract concerns, Casey Kasem left the show. Casey's last show aired August 6, 1988. Many radio stations and fans were upset. Casey joined the Westwood One radio network and created Casey's Top 40. As a replacement for Casey, ABC Radio Networks hired Shadoe Stevens.
Classic AT40 with Shadoe Stevens: August 13, 1988 through January 28, 1995
On August 13, 1988, Shadoe Stevens became the new host of AT40. Shadoe began the show by doing a "theater of the mind.":
Shadoe walked through an AT40 museum of sorts, describing the show's history along the way. Near the end of the tour, Shadoe saw a gold statue of Casey Kasem. The tour ended when Shadoe reached the studios where AT40 was recorded, and then the show's regular theme began.
The content of AT40 with Shadoe as host remained
basically the same, but some changes would occur during the next few
years. New features that debuted on Shadoe's watch included Flashbacks,
where Shadoe would play clips of the top 5 from a past show, AT40 Music
News, and AT40 Sneek Peek (sic), where Shadoe would
play the song added to most radio stations that week.
On July 1, 1989, AT40 became available to radio stations on the CD format for the 1st time. AT40 sent a letter to radio stations about the change. Each show was 4 CDs in length, with each CD containing an hours' worth of content. Eventually, CDs replaced vinyl completely.
Many of the radio stations upset by Casey's departure dropped AT40 in
early 1989 when "Casey's Top 40" debuted. Another
blow to AT40 occurred during the early 1990s, when major changes to the Top
40 format took place. Top 40 stations splintered into subformats,
including Top 40/Mainstream, Top 40/Adult, and Top 40/Rhythm. Rap and
Grunge became quite popular as well. At the same time, Billboard
decided to change the way it tabulated the Hot 100. Billboard was now
able to track how many copies of a single was sold as well as how many
times a song was played on radio stations. On November 30, 1991, the
revised Hot 100 debuted. Due to the methodology change, more rap and other
nontraditional Top 40 music now appeared in the top 40 positions of
In order to keep a similar pop sound, AT40 switched to an airplay-only chart, the Top 40 Radio Monitor, on November 30, 1991. However, this chart also included the nontraditional Top 40 music. Radio stations continued to drop AT40 and switch to Casey's Top 40 and Rick Dees Weekly Top 40. (Casey's Top 40 used the Radio and Records Top 40 pop (CHR) chart, which only measured airplay.) In January 1993, AT40 switched charts again, to the Top 40/Mainstream chart, also an airplay only chart. AT40 used this chart until the end of its run.
Also during this time, AT40 also tried to become more "hip" sounding and changed its jingles and theme. In the last week of June 1992, Shadoe announced some changes would occur next week. On July 5, 1992, the show's 22nd Anniversary, AT40 began with its new theme. Here is a memo describing the change to radio station program directors. However, all of this was not enough. AT40 was no longer heard in the USA after the summer 1994 (view a Billboard article announcing the change), and ended its run on January 28, 1995 (another Billboard article announcing the end of AT40).
AT40 was distributed internationally without the network commercials. During Shadoe's era, some of these had special sponsorship by the Pepsi Cola company, which also had special AT40 jingles that mentioned Pepsi. Some versions of AT40 had local hosts that used the native language of that country. In these situations, production elements (jingles, sound effects) would be sent to the station in cassette form.
A few specials aired during Shadoe's reign, including among others "The World Tour", "Book of Records 80s Edition", and "All-American Fourth of July Special". When Shadoe took vacations, guest hosts were either music stars such as Debbie Gibson or TV actors such as the late Jay Thomas.
From July 4, 1970 to January 28, 1995, 5363 songs made
the top 40, and
552 songs hit Number One. The first Number One song was "Mama Told Me
Not to Come" by Three Dog Night, and the final Number One was "On
Bended Knee" by Boyz II Men. For examples of important charts in AT40's
history, visit the chart
AT40 with Casey Kasem: March 28, 1998 to January 3, 2004
At the end of March 1998, "American Top 40" was revived by AMFM networks, and the show was again hosted by Casey Kasem. In fact, there were now 3 versions of the show. Besides AT40, which was based on the Top 40/Mainstream format, there were 2 "American Top 20"s. One version was based on the Hot Adult Contemporary format (Hot AC), and the other was based on the Adult Contemporary format (AC). These shows used the R&R charts. (From October 2000 to August 2001, the shows used unpublished Mediabase 24/7 charts). American Top 20 AC became American Top 10 in 2004.
The format of AT40 was very similar to Classic AT40 under Casey's reign. During this time, radio stations could receive shows via the internet as well as cd.
In order for the show to play correctly on the air, DJs
had to know the exact content and program length of the show. Included
with each show was a set of cue
sheets, which lists in detail each segment of the show and the playing
time of each track. These sheets also indicated how much time the
station had to play commercials in between each segment of the
Radio station personnel also had to communicate back to AT40s owners and let them know that they did play the show. One way they could do this is by sending a proof-of-play affidavit.
AT40 with Ryan Seacrest: January 10, 2004 -
In December of 2003, Premiere Radio Networks announced
that radio and television personality Ryan Seacrest would take over
AT40 in January 2004. AT40's format became more interactive, with
listeners voting on their favorite song via the internet and e-mail to
Ryan being read. From July 2020-June 2021, Ryan had a special AT40 Rewind segment
that highlighted events from AT40's 50 year history. Also, during this era, delivery of
the show switched to internet only for most clients.
Casey Kasem continued to host American Top 20 and American Top 10 through July 4, 2009 (for more info on these shows, see the history page on the AT20 section of this site).
Starting at the final weekend of 2000, classic AT40
shows were heard again. The 2nd half of the top 100 hits of 1985 was
played on several stations, especially stations with a 1980's lean.
Each week the show plays the final 3 hours of classic AT40 shows from
the 1980s. The show ended its run in December 2002. For more
information on the show, visit the Flashback
AT40 on Sirius-XM Satellite Radio
After a brief run on XM in 2003, AT40 returned to XM in August 2006. For the weekend of August 4, 2006, a marathon of shows was run on both the 1970s and 1980s channels. After the marathon, 1 show from each decade was run per week. Often, the shows are edited down, removing themes, jingles, and sometimes songs. Eventually after the Sirius-XM merger, the 1980s shows were no longer broadcast.
AT40: The 1970s and AT40: The 1980s
In late 2006, Premiere Radio Networks began producing a show similar to the old AT40 Flashback. Instead of the 1980s shows, entire 1970s shows were made available for radio stations to air. The only catch was that only 3 hour shows were available to air, meaning only shows before the 1978 switch to 4 hours are available. In 2012, 4 hour 1970s were made available to stations that wanted to air them. Many stations though still elected to only air the final 3 hours.
In April 2007, Premiere made 1980s shows available once again. The format is the same as the 1970s show above, and all 4 hours are available if wanted. More details about these shows can be found on this page.
Visit our tribute to the number one countdown show.
More Information on Classic AT40
Casey Kasem retired from current countdowns as of the July 4, 2009 weekend, ending the American Top 10 and American Top 20 shows. Here is a link to a remaining story about Casey's retirement: