**10.1 Costs of storage in sound archives**

**10.2 Format-specific preservation costs - a
first attempt**

**10.1 Costs of storage in sound archives**

*Cor L. Doesburg*** NOB, Hilversum**

**1. general **

If we obtain some insight into the costs of storing sound in an archive (meaning long-term storage), we do not exclusively deal with the costs of the information carrier but with the overall organisation of a sound archive.

Although the costs of an information carrier itself are not too high, the number of information carriers and storage capacity are not to be neglected whilst determining the overall cost.

The question is, however, what is the storage cost in relation to other "archive" costs.

In this report we concern ourselves in the first instance with only one aspect out of the overall cost price, namely: what costs are involved in information storage? - in other words, how can we define and quantify these costs? Further in this report we will co- ordinate this with the overall archive costs.

The answer to the question "why do we want to know" is supposed to apply to, for instance, management who will make the final and correct choice as to which information carrier should be used in an archive.

An important question is "what influence has the type of information carrier on the cost of sound storage?" It seems obvious that a miniature version of the information carrier (such as an R-DAT-cassette) should provide a solution to the available space problem. We have to prove, however, that this assumption is correct and in order to reach the correct decision, it is necessary that we determine the various calculation factors for sound storage and express these in a workable unit which can be the basis for an accurate definition. In this way it will be relatively simple to ascertain if the price of an information carrier is of great influence on the overall cost and if the operational qualities of that information carrier can be weighed against a cost reduction or a cost increase in the overall running cost.

**2. what deterrmines the archive costs? **

We can define the four principal areas of which cost development is more or less independent. These areas certainly have a mutual influence and each area is not isolated:

The total housing cost of an archive which holds the storage space.

The total number of staff working for the archive.

The raw materials which are necessary to operate, such as the purchase of tapes, forms and office equipment.

The sound equipment to be used in order to play-back the supplied information and to copy it onto the archive carrier.

Because it concerns a comparison between an analogue recording tape and an R-DAT cassette as archive carrier, our main interest at this stage is the calculation of the storage costs.

**3. which part of the storage cost do we want to calculate**

In order to calculate the storage capacity we need the following information:

The cost of storing the information carrier, in other words: the housing of carrier volume. One can express this possibly as hard volume.

It is more correct to calculate the actual cost of the ultimate "archive" product:

The cost of storing the information, in other words: the housing of information volume; this could be expressed as soft volume.

From the above, the following could be possible:

To express the storage of the carrier in the number of tapes per cubic meter housing, and when we know the capacity of an information carrier, we can express the information storage in number of hours of information per cubic meter housing capacity.

This is a handy prefix for calculation purpose.

**4. what will we actually do with these cost figures**

Calculating the storage costs in relation to the archive costs is a way to look clearly at the measures which have to be taken as to the quality or the continuity of the archive and to determine the importance of the effects of the measurements.

If we estimate, that in the coming decade we will have to deal with a decreasing margin between budget and cost; the following question could arise:

Should the storage costs per hour, which are dependent on housing costs in the long term: - be increased - be decreased - stay the same

If we issue the above mentioned estimate, we come to the decision that the storage costs should be decreased, in other words: the number of hours information per cubic meter housing should be increased!

**5. why does the number of hours of information per cubic
metre housing have to be increased?**

Archiving is always an expanding matter; every year new information to be stored is delivered to the archive. Advance selection of historic information is not simple; even more so when selecting after a certain time, and then destroying the information of lesser historical value: it costs time which is equal to money, which is not in relation to the storage costs of that information.

Only after a long time, when the information carrier has to be replaced, would be the right moment to effect this.

Another fact is, the expansion of storage space is always an abrupt action: we have to add more new cubic meters space and then have to wait until this space is used up again. We estimate, that the ratio between budgets and costs in future is decreasing. This is the final argument to reach the conclusion that "we have to store more information in the available space".

The increase in the number of hours of information per cubic meter of housing is only possible however, under the condition that this increase is made in such a manner that it is acceptable (considering other requirements needed for information storage).

Regarding the storage costs, we have not taken into account the following subjects:

The safety of the information; i.e. spheric saving information carriers against atmospheric conditions; against electronic failures and against fire and theft.

The handling costs of information; i.e. copying from an information carrier onto a consumer tape for lending out; search documentation systems and personal advice and administration.

The preservation of information; i.e. a technological system that will keep the information on a long-term basis.

The specific technical qualities of the various information carriers; i.e. special requirements of operating the equipment and the structural operating process, depending on the shape of the carrier (roll, disc or tape) and the recording technology (mechanical. magnetic or optical).

All these aspects are very important for running an archive in an operational way (for instance, search facilities and user-friendly service) and should certainly not be neglected at the final decision on archiving.

When deciding on the organisation of an archive one must weigh out the available means against the risk.

**6. summary **

Summarising this particular subject, storage costs, we have to mention that:

The main concern is the number of hours information per cubic meter of housing to be stored.

We have to deal with the information housing costs per cubic meter.

We have to deal with the storage capacity of the carrier, i.e. the number of hours of information that can safely be stored on the carrier.

We did not consider the operational costs for staff and machines.

**7. conclusion**

Just reviewing all that we have discussed concerning the specific subject of storing costs, we can make the following conclusions:

In view of the future expectations a reduction in housing cost is desirable.

The number of hours of information per cubic meter of housing has to be increased.

The storage capacity of an information carrier should be increased safely.

The operational costs are, as far as we know, not related to the storage costs. It remains to be seen, however, if operational costs can be decreased when using another information carrier taking into account the special operational aspect, such as user-friendly facilities.

**8. practical example**

A practical example is necessary for illustrating the purpose of the above-mentioned facts.

The figures are derived from an existing archive and are subject to the present work configuration. All figures in this example are rounded off: the only purpose is to observe the ratio between them.

The facts on this archive are:

The information carrier used is an analogue recording tape with one hour storage capacity.

The contents of the storage space - where cabinets and stands are installed - is 25 cubic meters.

The cost of housing the complete archive is Hfl.70.000,-- a year. (Dutch guilders).

The stored information is 12.500 hours.

When using these figures we can calculate that the number of hours of information per cubic meter housing is 12500/25 = 500 hours.

Considering that "one hour of information" is in fact the "final product" of the archive, all the housing costs of the complete archive should be charged to the product. In this way a cubic meter housing of storage space costs 70000/25 = Hfl. 2800,-- a year.

In this example the storage of one hour of information costs 2800/500 = Hfl.5,60 a year.

In this example it seems to be clear that - with the available space of the existing storage space in mind - when using an information carrier with a higher storage capacity, the number of hours of information stored can be increased and the result is a decrease in storage costs of one hour information a year.

An information carrier with a lot more storage capacity than the analogue recording tape which is used in this example, is the digital magnetic tape: the R-DAT (Rotary-head Digital Audio Tape). Except that the size of an R-DAT-cassette is remarkably smaller than a professional audio-tape: the recording capacity is three times as high as the analogue tape used in this example.

The R-DAT could be the ideal instrument for a remarkable increase of storage capacity in an archive.

Using the above mentioned figures we can make a reasonable comparison.

The measurements of the used analogue recording tape are 0,27 x 0,27 x 0,015 = 1,09 x 10-3 cubic meters.

The measurements of an R-DAT-cassette are 0,08 x 0,06 x 0,015 = 0,072 x 10-3 cubic meters.

The volume ratio between an R-DAT-cassette and an analogue tape is 1,09/0,072 = 15,19 . 1.

The maximum number of hours to be stored on an R-DAT-cassette is 3 hours. The information storage ratio between an R-DAT- cassette and an analogue tape is 3 x 15,19 = 45,57 : 1.

It is a fact, that storage capacity is reduced when storing smaller objects: inefficient space is increased. Because of past experience it is necessary to introduce a correction factor of 0,8.

The conclusion is, that the storage capacity of an R-DAT cassette in the same storage space is 36 times as high as the analogue tape we used in this example.

As far as we know, the price of an R-DAT-cassette is roughly the same as the price of the analogue tape used in this example. However, the effect of this can be found later in other costing.

Even the price of a professional R-DAT-recorder (ProDAT) is just as high as a professional analogue audiorecorder, which is normally used in archives. These cost effects will be shown later on.

We are neglecting the costs of new cabinets and stands that are especially needed for housing the R-DAT-cassettes. The most important fact is the possibility of increasing the storage capacity by 36 times and that results in the number of hours per cubic meter of housing in this example to be increased to 36 x 500 = 18.000 hours!

Taking into account the figure of housing per cubic meter being Hfl.2800,--, we can calculate that the storage costs of one hour of information on an R-DAT-cassette are 2800/18000 = Hfl.0,16 a year: a dramatic and attractive difference!

The example shows us the following:

* The storage costs using analogue recording tape are 36 x more expensive as when using the R-DAT-cassette in the same capacity storing space.

* the existing archive contents can be used longer than 36 years at present production level.

The result that - as in the case of using an analogue tape - no building activities have to be undertaken to expand the storage space is, of course, very attractive. If one has to do so, the housing costs per year are increasing only slightly. When recalculating we can compare the results with each other in order to make a decision. When we look at the storage costs only, and we do not take the other aspects of information carriers into account, the result of this competition is very clear!

**9. however**

We do remember:

**which factors determine the archive costs**

* The complete housing costs of the archive.

* The work structure and the overall personnel costs.

* The raw materials, such as tapes etc.

* The available equipment/machines.

If we want to review the situation clearly - the most important question is really: what are the actual storage costs in relation to the overall cost projection of the archive?

Again the given figures are derived from an existing archive practice and are rounded off, only for the purpose of illustrating the related ratio.

The other costs of the complete archive - as in the case of the used analogue tape - are as follows:

* The personnel costs: Hfl.750.000,-- a year.

* The remaining costs related to the safety copy archive, the overheads of a complete company, the purchase of raw materials such as tapes and forms, costs of the archiving documentation system, costs of a computer system, an office inventory, write-offs, etc. are approximately Hfl.580.000,-- a year.

* The technical costs, such as write-offs, maintenance etc. of the audio equipment are Hfl.150.000,-- a year.

Taking the storage capacity of 12,500 hours of information into account and considering that this information is the final product of the archive, we can calculate that the remaining costs for one hour of information are: 1480000/12500 = Hfl.118,40 a year.

If calculating the same costs while using an R-DAT-cassette we need to suppose in order to obtain a reasonable comparison that the stored information of 12.500 hours is equal to the yearly information production made by the staff. It is obvious that a 36- times production capacity is too much for the "historical events" taking place in a country. Of course this assumption could be arbitrary, but it is reasonably useful for the comparison.

The other costs in the case of use of the R-DAT-cassette are:

* The personnel costs: Hfl.750.000,-- a year.

* The remaining costs whereby purchase of R-DAT-cassettes for comparison is estimated on Hfl.50.000,-- less than in the case of analogue tape which are Hfl.530.000,-- a year.

* The technical costs remain at Hfl.150.000,-- a year.

The remaining costs for one hour of information in the case of R-DAT are 1430000/12500 = Hfl.114,40 a year.

**Summarising**:

In the case of the used analogue tape the total archive cost for one hour of information is: Hfl.5,60 + Hfl.118,40 = Hfl.124.-- a year.

In the case of R-DAT the total archive cost for one hour of information (considering an equal year production) is: Hfl.0,16 + Hfl.114.40 = Hfl.114,56 a year.

The difference between using an analogue tape or an R-DAT- cassette as information carrier per hour of information is Hfl.9,44 a year. So every year gives a saying of 12500 x 9,44 = Hfl.118.000,-- on the total amount. For a good understanding of the ratio we have taken into account that the total archive costs are Hfl.1.500.000,-- a year.

As to the above mentioned statement "that in the case of an analogue tape, the information storage space would have to be increased, as opposed to the decrease in space when using an R-DAT, we can see the relation between the yearly housing costs of Hfl.70.000,-- and the overall yearly archive costs.

Taking all the above mentioned arguments into account we have to consider that when using an R-DAT-cassette as a long-term storage instrument, there is no real technical experience at present and the technical problems are, as yet, unknown. Most technicians have their doubts.

**10. final conclusion **

Reviewing the above, the final conclusion is:

* The storage costs per hour of information are marginal for analogue recording tape in relation to other costs of the archive.

* The storage costs per hour of information are, when using R-DAT, even more marginal in relation to the other costs of the archive.

When all other aspects of both types of information carriers are taken into consideration and compared to the eventual financial effects, the conclusion has to be:

The technical - and operational aspects of the type of information carrier are important to the overall functions of the archive.

The economical aspects, of the type of information carrier are - in their totality - marginal for the overall continuity of an archive.

Other companies producing software-like products such as radio and television programs have in many cases come to the same conclusion.

In other words: from a very narrow perspective, we came to the conclusion that the storage costs are of course useful. However for the complete functioning of an archive we have to examine the total amount: not the "figures" only.

If there is a need to save costs: the "personnel costs" and the "remaining costs" can be more effective.