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Originals

World
Table 1: World

Media Type
Number of Stations
Unique Items per Year
Conversion Factor
Total Terabytes (Annual)

Lower Bound
Upper Bound
Radio (CIA Factbook 2000) 43,973 65.5 million hours of original programming .05 GB/hour 3,274 3,274
Television (broadcast only) (CIA Factbook 2000) 33,071 48 million hours of original programming 1.3 GB - 2.25 GB hour 62,769 108,638
Total:    66,043 111,912


Table 1: United States

Media Type
Number of Stations
Unique Items per Year
Conversion Factor
Total Terabytes (Annual)

Lower Bound
Upper Bound
Radio (FCC, 1999) 12,600 15.8 million hours .05 GB/hour 788 TB 788 TB
Television (broadcast and cable networks) (FCC, NCTA, 1999) 1,884 3.4 million hours of original programming 1.3 GB- 2.25 GB/hour 4,470 TB 7,736 TB
Total:    5,258 8,524 TB

Radio

Conversion Factor

Each hour of audio requires about 50 MB, if stored at MP3 quality. (Different sources cite different figures, depending upon assumptions made about compression and sound quality.)

World

There are 43,773 active radio stations in the world, according to the CIA World Factbook 2000: about 16,500 AM stations, 26,000 FM stations, and 1,500 shortwave stations.

We estimate that FM radio stations broadcast 20 hours per day, AM stations 16 hours per day, and shortwave stations 12 hours per day. Therefore, there are approximately 290 million hours (188 million FM, 98 million AM, and 6 million shortwave) of radio programming per year. Applying the 50 MB/hour rule of thumb, one may estimate an annual storage requirement of about 14,500 TB if one were to record everything broadcast on the radio.

United States

As of 1999, there are 12,615 radio stations in the United States, according the Federal Communications Commission: 4,783 AM, 5,766 FM and 2,066 FM Educational stations. As noted above, the two formats broadcast different numbers of hours each day: 20 hours for FM stations, 16 hours for AM. Total US broadcasting hours would therefore be roughly 85 million hours per year. Again, each hour of broadcasting would require 50 MB of storage, using the MP3 format. Total storage required for all US radio broadcasts is about 4,300 TB.

About 84% of US radio stations have music as their primary focus, and provide little original content. (Source: Radio Marketing Guide & Fact Book, Radio Advertising Bureau 2000-2001) The remaining 16% are news, talk and religious stations, providing, presumably, almost 100% "original" information each day. Regardless of format, a percentage of most stations' broadcast time includes some commentary, weather reports, news updates, and traffic reports - perhaps an average of 5 minutes per hour. In addition, radio stations average between 12 and 16 minutes of commercials per hour. We can use this information to estimate how much "original" programming appears on the United States radio airwaves:15.8 million hours. (This estimate excludes advertisements and music.) The equivalent in bytes is 788 TB.

Television

Conversion Factor

Satellite TV transmits between 3 and 5 mb per second. Therefore, one hour of broadcasting will require 10.8-18 Gbits of storage (compressed to MPEG-2). We can estimate about 1.3 - 2.25 GB per hour of TV broadcasting. Source: Internet Archive.

World

There are 33,071 television stations in the world, according to the CIA World Factbook 2000. If these stations broadcast about 16 hours per day, this would equal about 193 million hours total programming. We estimate about 1/4 of the programs are "original," - this is 48 million hours each year. Estimating that one hour of video requires 1.3 GB of storage, then worldwide, program storage would be about 63,000 TB; using the 2.25 GB estimate, it would be about 109,000 TB.

United States

As of 1999, there are 1,616 broadcast television stations in the United States, according the US Federal Communications Commission. This figure includes the major networks (ABC, CBS, NBC, FOX, PBS and newcomers WB, UPN and PAX), the networks' affiliates, as well as local and public broadcasting stations. In addition, the National Cable Television Association reports that there are 210 national cable networks and 54 regional networks, as of August 2000. (54 more cable networks are planned but not yet operational.)

If all 1,884 of these stations broadcast 20 hours per day, that would equal just under 14 million hours per year. We estimate that about 1/4 of the television programs broadcast are "original" - this is 3.5 million hours each year, equivalent to between 4,400 and 7,800 TB.

Stock

In 55 years of programming, the networks have accumulated the following stock of material (Source: Library of Congress Report, Television/Video Preservation Study: Volume 1: Report, October 1997).
Table 3: Stock of Material Accumulated by the Major Networks.

ABC
1,037,000 films/tapes
CBS 1,045,000 tapes and more than 150,000,000 feet of film
NBC 600,000 film reels (currently estimated at 100,000,000 feet) and 1,600,000 videotapes

Meanwhile, some of the major studios have accumulated original materials as well:
Table 4: Materials Accumulated by the Major Studios.

Disney
6,500 television programs on 80,000 reels and tapes
Fox 54,000 television programs on 780,000 reels and tapes
MCA/Universal 18,000 (through 1994) television programs on 217,000 reels and tapes
Paramount (Viacom) 8,000 television programs on 1,200,000 reels and tapes
Sony/Columbia 35,000 television programs on 600,000 reels and tapes
Turner Entertainment 20,000 television programs on 337,000 reels and tapes
Warner Brothers 28,000 television programs on 1,000,000 reels and tapes

These figures overlap, of course, with those we have compiled for magnetic tape.

As of 1998, there are well over 18,000 hours of programs in syndication available to be aired. This is equivalent to 18 TB of information. (Source: Television and Video Almanac 1998)

Rate of Change

The number of radio stations and broadcast television stations in the United States has increased slightly - between 1 and 2% - every year since 1990.

While the number of cable television systems has decreased since 1993, the number of cable networks (i.e. channels) has increased annually. 54 new cable networks are scheduled to be launched in the coming year.


Copies

Radio

World

We estimate that FM radio stations broadcast 20 hours per day, AM stations 16 hours per day, and shortwave stations 12 hours per day. Therefore, there are approximately 290 million hours (188 million FM, 98 million AM, and 6 million shortwave) of radio programming per year. Applying the 50 MB/hour rule of thumb, one may estimate an annual storage requirement of about 14,500 TB if one were to record everything broadcast on the radio.

United States

As of 1999, there are 12,615 radio stations in the United States, according the Federal Communications Commission: 4,783 AM, 5,766 FM and 2,066 FM Educational stations. As noted above, the two formats broadcast different numbers of hours each day: 20 hours for FM stations and 16 hours for AM. Total US broadcasting hours would therefore be roughly 85 million hours per year. Again, each hour of broadcasting would require 50 MB of storage, using the MP3 format. Total storage required for all US radio broadcasts is about 4,300 TB.

Television

World

There are about 33,000 television stations in the world (including some but not all cable stations), according to the CIA World Factbook 2000. This means that there are approximately 193 million hours of television programming per year (assuming each station broadcasts 16 hours per day). Estimating that one hour of video requires 1.3 - 2.25 GB of storage, then worldwide, television would require between 250,000 and 435,000 TB.

United States

As of 1999, there are 1,616 broadcast television stations in the United States as well as about 260 cable networks operating on nearly 10,500 cable systems. Each station broadcasts an average of 7,300 hours per year (again estimating 20 hours of broadcasting per day). If one wished to capture all of the programming generated by every station and cable system, regardless of duplication, it would be about 88 million hours, requiring between 114,000 and 198,000 TB of storage.


Fun Facts about Broadcast Media.

Television
  • For many years, most large TV stations and the major networks subscribed to the Code of Good Practices of the National Association of Broadcasting, which established limits on the number of commercial minutes that could be telecast each hour. The limits were voluntary but widely followed: 9 1/2 minutes of commercials during primetime; higher amounts during other times of night and day. In 1992, however, the guidelines were ruled a violation of Federal antitrust law. Throughout the industry, most pledged to continue the limits - but gradually that eroded, as networks added more ad time. Prime time today has an average of 15 minutes of ads per hour. The FCC regulates advertising only during children's programming: 10.5 minutes/hour on weekends, 12 minutes/hour on weekdays. (Source: Gerald Baldasty, University of Washington http://faculty.washington.edu/baldasty/Feb3.htm)
  • Approximately 7 in 10 television households, more than 65 million households, subscribe to cable. (Source: National Cable Television Association)
Radio
  • There are currently more than 4,500 streaming radio stations on the Internet, distributed as follows: Africa (16); Asia (109); Europe (970); North America (2,786); Oceania (235); South America (166) and Internet Only (313). (Source: RadioDirectory, http://www.radiodirectory.com/Stations/)
  • "Talk radio," in which celebrities and experts from various fields answer listener "call-in" questions and offer their advice on various topics, has grown spectacularly in recent years. The "call-in" format is the fastest-growing in radio, accounting for nearly 1,000 of the 10,000 commercial radio stations in the United States. (Source: U.S. MEDIA IN THE 1990s: THE BROADCAST MEDIA By Fredric A. Emmert, US Information Agency)
  • 6,108 new radio stations have been started in United States since 1970 (Source: Arbitron Ratings, http://www.arbitronratings.com)
  • The average US listener 12 and older hears approximately 1,100 hours of radio each year. (Source: Arbitron Ratings, http://www.arbitronratings.com)
  • Since 1996, commercial spot loads have averaged 12-16 minutes per hour. These averages can be even higher during morning and afternoon drive hours. (Source: "An Analysis of the Effects of Consolidation on the Radio Industry" http://mmstudio.gannon.edu/~gabriel/rapela.html.)

Bibliography

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