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About the Project



Originals

Flow

Tape

Analog
    Video

    In the year 2000, 1.4 billion blank VHS video tapes will be produced for the entire world. If all of these tapes were filled to their 120 minute capacity and then converted to digital using MPEG-2 compression, there would be approximately 4 gigabytes of data per tape. One year's production of blank videotape, therefore, provides storage space adequate for 5600 petabytes of data.

    Assuming twenty percent [???] of this tape is used for the storage of original data, the flow of new data stored on analog VHS videotape per year would be 1120 petabytes.

    Video camcorder tapes (all formats except VHS) are produced at the rate of 150 million per year according to the Japan Recording Media Industry Association. Almost all of this tape is used for the storage of original data. Assuming one hour per tape in MPEG-2 format yields 300 petabytes.

    Total original analog video production worldwide runs at about 1420 petabytes annually. [???]

    Audio

    In the year 2000, 921 million blank audio tape cassettes will be produced for the entire world according to British research firm, Understanding & Solutions. If all of these tapes were filled to their 120 minute capacity and then converted to digital using the common CD audio format, there would be approximately 1 gigabyte of data per tape. One year's production of blank audiotape, therefore, provides storage space adequate for 921 petabytes of data.

    Assuming twenty percent [???] of this tape were used for the storage of original data, the flow of new data stored on analog audiotape per year would be 184.2 petabytes.

Digital

    There are 25 million computer tape drives installed in the world at present. These drives provide storage capacity for all range of computers - from desktop personal computers to the most mammoth supercomputers. Fred Moore estimates that the amount of data stored on tape is between 4 and 15 times the amount of enterprise data on disks and that there is about $1 billion per year of computer tape media sold worldwide.

    In order to estimate the amount of data stored on tape, we will first estimate the number of enterprise storage systems and then multiply by 10. IDC estimates that 250 petabytes of RAID storage capacity will be shipped worldwide in 2000. RAID storage systems are taken as most closely approximating the storage capacity deployed to data-intensive corporate, government and scientific uses, the largest consumers of magnetic tape backup.

    A midrange estimate of the total amount of data stored on magnetic tape would, therefore, be 2.5 exabytes.

    In all but the largest computer applications, however, tape is generally used solely for backup of data already stored on hard disk drives. Quantum, the manufacturer of DLT tape, the most popular format for enterprise storage, estimates that 90 percent of the tape capacity in that format is used for backup. Fred Moore also points out that it is more and more common for multiple copies of data to now be stored on tape.

    If it is assumed that ten percent of the total amount of data stored on tape is original data of the sort generated by scientific experiments in high-energy physics or by observational earth satellites or archival storage on tape where the data is no longer stored on disk, original magnetic tape data is roughly the same as all the RAID capacity shipped annually - 250 petabytes in the year 2000.

    250 petabytes is also generally consistent with estimates derived by use of forecasts of producer revenue of around $1 billion for tape media and an average cost of around $5 per gigabyte of tape storage.

Disks
    Floppy Disks

    In the year 2000, 1 billion 3.5 inch floppy disks, each capable of storing 1.44 megabytes, will be produced for the world. This is an aggregate storage capacity of 1.4 petabytes. If [???] five percent of this is original data, new data per year on floppy disk would be 0.07 petabytes.

    Removable Disks

    In the year 2000, 88 million removable 100 megabyte disks and 25 million removable 1 gigabyte disks will be produced for the world. Together, these two varieties of removable disks provide 33.8 petabytes of storage capacity. If five [???] percent of this is original data, new data per year stored on removable disks would be 1.69 petabytes.

    Hard Disks

    In the year 2000, hard disk drives capable of storing 2500 petabytes of data will be produced for the world.

    The amount of original data stored on hard disks is most likely to vary according to the computing environment in which the disks are deployed. It is possible to divide all hard disk storage into three categories:

    1. Personal computer, laptop, or workstation. This type of computer is responsible for approximately 55% of the computer disk storage capacity currently shipped.
    2. Departmental server. This class of computing environment is responsible for about 30% of the overall storage market.
    3. Enterprise server. These big computers account for about 15% of the hard disk storage.

    As with all such broad categorizations, there may be quite a bit of blurring around the edges. However, consideration of these three different environments leads to the conclusion that the amount of original data stored on the computers in each is probably substantially different.

    Single user computers and the applications software usually found on them is not suited for the production of large amounts of original data. A recent study (McKenzie, "Microsoft's 'Applications Barrier to Entry': The Missing 70,000 Programs") found that most people used only a few applications other than those found in the Microsoft Office application suite. These applications are usually text-based, such as word processing or spreadsheets, and so require minimal storage space. Most personal computers now sold come with hard disk storage capacity in the range of 10 gigabytes. 100 megabytes of original data constitutes 1 percent of disk capacity, which is the estimate for this category of computer disk. [???]

    Departmental servers would be commonly found in business, government, educational or other organizational settings. These servers provide disk space for a group of users, who all contribute to the production of organizational data. Aside from the databases and spreadsheets, there may be product catalogs and other graphic intensive marketing material, PowerPoint presentations, and so on. An estimate of the original data stored in these hard disks is 35%. [???]

    Enterprise servers are the large-scale computing environments where "big iron" traditionally has reigned. The applications here are corporate or governmental transaction processing on a large scale or the generation of huge data sets from scientific research missions. The amount of original data stored on these computers is estimated at around 65%. [???]
Table 1: Original Data Stored On Hard Disk By Computing Environment (1995-1999) [In Petabytes]

 

Original Data

1995

1996

1997

1998

1999

Total

Original

Total

Original

Total

Original

Total

Original

Total

Original
Personal 1% 58 0.6 101 1 189 2 399 4 766 8
Departmental 35% 32 15 55 19 114 40 239 84 460 161
Enterprise 65% 16 8 27 17 41 27 86 56 167 109
Total:   105 23.6 183 37 344 69 724 144 1,393 278


Table 2: Original Data Stored On Hard Disk By Computing Environment (2000-2004) [In Petabytes]

 

Original Data

2000

2001

2002

2003

2004

Total

Original

Total

Original

Total

Original

Total

Original

Total

Original
Personal 1% 1,405 14 2,553 26 4,466 45 7,165 72    
Departmental 35% 843 295 1,532 536 2,680 938 4,299 1,505    
Enterprise 65% 306 199 557 362 974 633 1,563 1,016    
Total:   2,554 508 4,642 924 8,120 1,616 13,027 2,593    
    The amount of original data compared to the total amount of data stored on magnetic hard disks works out to twenty percent over all the years under consideration. Accordingly, in the following table summarizing the annual flow of original data in various media, 20% of all hard disks are assumed to store original data, the actual amount will vary depending on the capacity of the hard drive itself.
Table 3: Original Data Flow Storage Estimates

Media Type

Unique Items per Year

Conversion Factor

Total Annual Petabytes (World)
Blank Audio Tape (2000) 184,200,000 1 gb per tape (CD audio format - no compression) 184.2
Blank Video Tape (2000) 355,000,000 4 gb per tape (MPEG-2 compression) 1420
Computer Tape Drives (2000) 5,000,000 Varies 250
Floppy Disk (2000) 5,000,000 1.44 mb per disk 0.07
Removable Disks (2000) 4,400,000

1,250,000
100 mb (low capacity)

1 gb (high capacity)
1.69
Hard Disks (2000) 37,400,000 Varies 500


Stock of Originals

Tape

Analog
    Video

    [???] 10 billion video cassettes, both prerecorded and recorded at home, have been accumulated. This is equivalent to about five years production of these tapes. One billion camcorder format tapes have also been added over the same time. This would be equivalent to 3 billion hours of stored original video, which if digitally encoded would produce a stock of about 6000 petabytes of original videotaped data. [???]

    Audio

    The total stock of original audio content stored on tape may be estimated by assuming twenty [???] percent of five years production of blank cassette tapes contains original content. This equals 1 billion cassette tapes. The digital equivalent of this audio information is 1000 petabytes.
Digital
    The stock of original data on magnetic tape may be approximated by adding the yearly flow of original data over the course of the expected lifetime of the medium. Some unfortunate experiences with the loss of computer data stored on magnetic tape has led to the practice of continuous migration of this data to new media every five to ten years. This process leads to the reduction in the number of tape cartridges that need to be managed as tape capacity inexorably rises as well as insuring modernization of the tape format.

    Therefore, the stock of original data on magnetic tape may be taken as five year's worth of original data flow. [???]
Disks
    Floppy Disks

    Floppy disks useful life is estimated to be three years. The amount of original data stored on the 4.5 billion floppies produced over the course of the past three years is around 5 percent of the total data on those disks, or 0.32 petabytes.

    Removable Disks

    The amount of original data stored on removable disks over the past three years is approximately 5 petabytes.

    Hard Disks

    Over the past three years, hard disk capacity of 4625 petabytes has been produced. If twenty [???] percent of that capacity has been used to store original content, the stock in that format is now 925 petabytes.


Copies

Flow

Tape

Analog
    Video

    In the year 2000 1.8 billion prerecorded video tapes will be distributed worldwide according to the International Recording Media Association. This entire production will be copies, principally of feature films. If converted to digital using MPEG-2 compression, prerecorded videotape would consume 7,200 petabytes per year.

    If [???] 80 percent of the blank videotape distributed per year were used for copies, this would constitute a digital equivalent of 4,480 petabytes.

    The total yearly world production of copied data on analog videotape, therefore, is 11,680 petabytes. [???]

    Audio

    In the year 1999, 125 million prerecorded audio cassette tapes were distributed in the United States according to the Recording Industry Association of America. This entire production was copies, principally of music. If converted to digital using audio CD format, and assuming about one hour of music per tape, prerecorded audio tape would consume 62.5 petabytes per year.

    If 80 percent [???] of the 921 million blank audiotapes distributed per year worldwide were used for copies, this would constitute a digital equivalent of 737 petabytes.

    The total yearly production of copied data on analog audiotape, therefore, is 800 petabytes.
Digital
    If ninety percent of the computer tape distributed annually were used for copies, this would constitute 2.25 exabytes of copied data for the year 2000. The amount of data on tape, however, is calculated by reference to the RAID storage capacity shipped, which has been rising rapidly. Similar trends will most likely be seen in the amount of data stored on tape, particularly as it becomes more common to make multiple tape copies of data.
Disks
    Floppy Disks

    If 95 [???] percent of the 1.4 petabytes of annual floppy disk storage were used for copies of data, this would add 1.33 petabytes to the stock of digital data stored on floppy disks.

    Removable Disks

    If 95 [???] percent of the 33.8 petabytes of annual removable disk storage were used for copies of data, this would add 32.1 petabytes to the stock of digital data stored on removable disks.

    Hard Disks

    If 80 [???] percent of the 2500 petabytes of annual hard disk storage were used for copies of data, this would add 2000 petabytes to the stock of digital data stored on hard disks.
Stock of Copies

Tape

Analog
    Video

    Five years production of blank T-120 VHS videotapes is approximately 7 billion units. If 80 [???] percent of this were used for storage of copied data, the total stock of such data in MPEG-2 conversion would be 2240 petabytes. Five years production of prerecorded videotapes is approximately 8 billion units. This is the digital equivalent of 3200 petabytes. The total world stock of copied data on videotape is 5440 petabytes.

    Audio

    The world production of blank audiotape for the past five years is approximately 5 billion units. There has also been sales of prerecorded audiotapes during that period of 6 billion units. Assuming that 80 [???] percent of the blank audiotape has been used for the storage of copied data, the overall stock of copies of audio data on tape is 4000 petabytes on blank tape and 6000 petabytes on prerecorded tape. Therefore, there is a total stock of 10,000 petabytes of copies of audio data on magnetic tape.
Digital
    Ninety percent of the data stored on tape is copies and tape is estimated to store 4 to 15 the amount of enterprise data on hard disk. IDC estimates that approximately 400 petabytes of RAID have been shipped in the past three years. If all data on tape is calculated as ten times that amount, or 4 exabytes, and copies as 90 percent of that overall amount, copies of data on magnetic tape worldwide would be 3.6 exabytes.
Disks
    Floppy Disks

    There have been 4.5 billion floppy disks produced in the last three years, creating a total storage capacity of 6.5 petabytes. If 95 percent of that storage were used for copies, the total stock of copies on floppy disk would be 6.1 petabytes.

    Removable Disks

    Over the past three years approximately 100 petabytes have been stored on removable disk. Assuming that 95 [???] percent of that is backups and copies, the total stock of copied data in this media format is 95 petabytes.

    Hard Disks

    Over the past three years, hard disk capacity of 4625 petabytes has been produced. If eighty [???] percent of that capacity has been used to store copies of data, the stock of copied data on hard disk is 3700 petabytes.
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