House of Commons - Science and Technology

Select Committee on Science and Technology Second Report

CHAPTER ONE: THE CENTURY DATE CHANGE PROBLEM

3. The cause of the century date change problem sounds deceptively trivial. In the early days of computing-the 1960s and 1970s-computer memory and disk space were expensive. Consequently programmers developed shorthand ways for representing information. One way in which this was done was to store years as two digits rather than four so, for instance, '1967' became '67'. This saved valuable memory for processing data and disk space for storing it. Programmers at that time did not expect the systems they were developing to remain in use for more than a few years. However the two digit convention persisted; partly because it became common, indeed standard, practice and partly because many of the systems now in use are based on, or use components from, older systems. Thus many of the systems which are today an integral part of our daily lives use only two digits to represent the year. In these systems, when the date changes from 1999 to 2000 the new year will be represented as 00. The effects that this will have on unmodified systems are difficult to predict, but could fall into one of a number of categories, for instance:

some will default to 1900, or some other incorrect date, rather than to 2000;

others will give unpredictable results when performing arithmetical operations or comparisons on the basis of two digit years, possibly with the loss or corruption of data;

some systems may be able to cope but these are not easily identified without thorough checking.

4. Century date change problems could occur in a wide variety of systems, components and circumstances. Computers from the most powerful mainframes to the humblest personal computer (PC) may have problems. Electronic control systems-such as those in heating systems, fax machines or video recorders-use microprocessor chips which may have date problems built into them, even if they have no apparent date or time dependency. Such so-called 'embedded systems' are widely found in more complex, possibly safety-critical, monitoring and control systems used in industry.

5. The majority of our witnesses, including many from well-known organisations such as Shell UK, SmithKline Beecham, Barclays Bank, Sainsbury's and the BBC, agreed that the century date change posed a genuine and significant problem, although there were slight differences in their assessments of scale and extent.[2] For instance, Morgan Stanley told us that "to date, we have encountered Year 2000 date problems in nearly all of our internally developed systems ... we have also found that networks, telecommunications infrastructure, and building systems are affected. In fact, the central building management system in our ... office which controls and monitors fire alarm, water detection and other safety systems has defective embedded chips".[3] Hundreds of major organisations from both the public and private sectors across the UK and abroad have tested their systems for millennium compliance, have found them wanting, and have committed substantial resources to remedial action. So while some systems, including those without any manifest or embedded date capability, will continue to function normally over the millennium, we find the evidence that the century date change presents a genuine risk of malfunction in automated systems which have a date function overwhelmingly convincing.

The Nature of the Problem

6. Many of our witnesses agreed that, superficially, the century date change presents a series of isolated technical problems to which there are technical solutions: "all individual technical date change problems are solvable".[4] However the majority, including BT, the Chancellor of the Duchy of Lancaster, and Railtrack, also agreed that the century date change is neither a single nor just a technical problem.[5] Computers have become ubiquitous-"we live in an automated world and microchips have permeated nearly all areas of our personal and business lives".[6] So while the causes of the problem are technical, the consequences of a failure to correct systems could extend throughout the business, economic and social spheres. Simultaneous and extended failures in key systems could present a risk to personal health or well-being as well as to future economic performance. The greater challenge, therefore, is not the correcting or replacing of faulty software and hardware but managing the process of implementation and completion of remedial action with the resources available and within the time remaining.[7] As the NHS Confederation told us the "Year 2000 is mainly a problem of management. The technical changes tend to be fairly simple but organising, implementing and paying for them is difficult".[8]

7. Many witnesses pointed out that, even if an organisation ensured that all its own systems were millennium ready, it would still not be possible to guarantee that it was not affected by century date change related problems. For instance, IBM told us that they must "also ensure that their systems are not contaminated by two-digit dates from computers linked to their own by public or private network".[9] This information chain aspect of the problem not only affects organisations where their networks are directly connected to others. A date change related failure which causes one particular company to have errors, for example in ordering, dispatching or paying for goods or services, could have severe consequences to other, millennium compliant, companies in the supply chain. This may be a particular problem for organisations which hold minimal stock and rely on 'just in time' deliveries as they may not have the ability to withstand even minor delays in deliveries or collections.[10] Morgan Stanley told us that "external product and service providers represent one of the greatest areas of risk"[11] and, similarly SmithKline Beecham stated that "arguably the biggest threat to our company comes from non-compliant suppliers, customers and other business partners".[12] Thus the implications of non-millennium compliance are wider than a single business. Companies cannot continue to trade if their suppliers cannot provide the goods they need or customers are unable to purchase their products. Left uncorrected, century date change problems could affect the integrity of entire business chains.

8. Such inter-dependencies between organisations are not restricted to the UK.[13] Many organisations rely on suppliers, service providers, customers or business partners in other countries: for instance, Marks and Spencer told us "we deal with ... a long international supply chain, on whom we are dependent for merchandise and services"[14] and EDS that its operations in the UK "could be seriously affected by the failure of other countries to fix their problems".[15] Moreover, any organisation with business connections overseas is likely to depend on international telecommunications and banking systems which themselves have to be made millennium ready. As the British Bankers' Association (BBA) stated "it is difficult to exaggerate the scale of the impact on banks and through them the UK economy if they and their customers and counterparties ... abroad are not Year 2000 compliant".[16]

9. It is the combination of these factors-the immutable deadline, the worldwide context and complex inter-dependencies-that makes managing the century date change "a challenge without precedent".[17]

When will Problems Occur?

10. Many information technology applications have the capability to look forward, or calculate long-term projections, well beyond the millennium and consequently some systems that are not millennium compliant may fail before the century date change itself. As IBM told us "really the issue of the Year 2000 is not the issue of the calender event; it is the question of whether or not the computer system can process a date which is beyond December 31, 1999".[18] There are already anecdotal examples of errors arising from inabilities to manage the century date change such as instances of credit card payments not being processed properly because the expiry date on the card was beyond 31st December 1999.[19] According to a survey undertaken by PA Consulting, 86% of organisations in the UK believe that they will experience some century date change related errors before the Year 2000.[20]

11. The difficulties that computer and embedded systems may have with the century date change from 1999 to 2000 is certainly the most easily recognised aspect of the Year 2000 problem but there are other critical dates which could trigger system errors. For instance, systems which handle the century date change perfectly could be affected by problems associated with managing dates around 29th February 2000. Past century base years-such as 1800 and 1900-although divisible by four, were not leap years but the millennium base year is. So, whilst much of the speculation over the century date change problem has focussed on what may or may not happen at midnight on 31st December 1999, and it is indeed likely that some systems will actually stop functioning normally at this time, in practice the precise time of the 'millennium moment' may well go relatively unnoticed (in computer terms at least). Other dates which witnesses considered to be potentially critical are listed in annex A.

Millennium Compliance

12. The British Standards Institute, in collaboration with a number of other organisations, have developed a definition for Year 2000 conformity (see annex B). This definition stipulates that "Year 2000 conformity shall mean that neither performance nor functionality is affected by dates prior to, during or after the Year 2000".[21] We agree that the ideal would be for all systems to manage the century date change properly-that is to be 'millennium compliant'. It is, however, arguable whether it is necessary, or indeed possible, to ensure that all existing systems meet such an exacting criterion. In some cases it may be more effective to replace existing systems which are not, or have not been proven to be, millennium compliant with new systems that will manage the century date change correctly. In other cases, where non-compliance is unlikely to affect performance or where the system is only of minor significance, leaving non-compliant systems in place may be acceptable. The key objective is that individuals and organisations are adequately prepared for the millennium-'millennium ready' rather than millennium compliant-and equipped with compliant systems or prepared to manage the consequences of non-compliance. The challenge that faces us, then, is to ensure that computer and embedded systems function in a manner that allows central Government, local government (including essential social services), businesses and society to continue to function as normally as possible now, over the millennium and afterwards.

2 eg. Ev.p. 183. Back

3 Ev.p. 168. Back

4 Ev.p. 105. Back

5 eg. Ev.p. 147. Back

6 Ev.p. 141. Back

7 Ev.p. 227. See also eg. Ev.pp. 130 and 138-9. Back

8 Ev.p. 78. Back

9 Ev. p. 57. Back

10 Ev.p. 151. Back

11 Ev.p. 168. Back

12 Ev.p. 185. Back

13 eg. Ev.p. 131. Back