Last Wednesday, in case you didn't notice, was 20/10/2010 – a numerically interesting date chosen by the UN to mark its first ever World Statistics Day.

Along with lies and damned lies, statistics often get a bad press. You can prove anything with statistics, people say. There may be a grain of truth in that, but governments and businesses can't sensibly make decisions and plans, or allocate resources properly without reliable data.

Imagine trying to govern a country that lacks adequate statistics about economic activity, healthcare, crime, education, urban development and environmental pollution.

Imagine a country that relies heavily on tourism but has no figures showing why people visit or what they think of their stay.

Imagine a country that relies heavily on agriculture, and yet has produced no data on the quality of cultivable land since the 1970s.

The country I'm talking about here is Egypt, though the same could probably be said for many developing countries. Last week, a report for the Egyptian cabinet highlighted a lack of accurate data in almost every area of activity. The report spoke of an epidemic of ineptitude among researchers and experts, and the scale of the deficiencies was horrifying, if not altogether surprising.

The lack of basic information in Egypt is an obvious barrier to economic and social development, as prime minister Ahmed Nazif (one of the more technocratic members of the regime) clearly recognises. Doing something about it, though, is not so easy.

For a start, there are various practical difficulties in countries such as Egypt. Having a vast, inefficient and largely paper-based bureaucracy doesn't help. Nor does the rampant corruption, where officials may have their own reasons for not keeping accurate records.

But there's more to the problem than that. One important factor is a general aversion to transparency, especially among authoritarian regimes such as the one running Egypt. Transparency leads to public debate and gives people the informational tools to question government decisions – an unwelcome state of affairs for those in power.

At the same time, a regime that can't be held accountable for its decisions doesn't necessarily see a need for accurate information on which to base its decisions: witness the Egyptian regime's irrational and unnecessary slaughter of all the country's pigs at the height of the swine flu panic, in spite of all the evidence that pigs were not to blame.

There are also some issues the Egyptian government (and others like it) would rather not talk about – and having no statistics is as good an excuse as any for shuffling them under the carpet. Sectarian tensions are one example that is considered too sensitive for thorough analysis. Egypt has no official statistics for the number of Christians among its citizens, though the total plainly runs into the millions. There is also a lack of government data on sectarian hotspots (though one Egyptian website has recently taken on the task itself).

Similarly, there has been no official census in Lebanon since 1932 – for fear of what it might reveal about changes in the sectarian balance.

Not compiling statistics is one issue; unreliable statistics are another. Some governments manipulate their figures in extraordinarily blatant ways. On my first visit to Yemen, an official gave me a booklet about the country's agriculture: how much land was devoted to which crops, etc. Interestingly, there was no mention at all of the most lucrative crop, qat, which they apparently didn't want foreigners to know about.

There's a deep-seated belief in many countries that statistics are dangerous – so dangerous, in fact, that efforts to compile them by non-governmental bodies and independent researchers must be strictly controlled. Last year, for example, copies of two magazines were seized in Morocco for publishing an opinion poll showing that 91% of Moroccans had a "positive or very positive" opinion of the king's performance. Despite the high approval ratings for the king, his performance was not deemed a suitable matter for public discussion.

Opinion polls on all manner of subjects are part of the daily news in many countries, and nobody needs permission to conduct them. In some parts of the world, though, the questions have to be vetted by the authorities. When Gallup carried out an international poll a few years ago, for example, the authorities in Morocco, Saudi Arabia and Jordan would not allow pollsters to ask: "Do you believe news reports that Arabs carried out the September 11 attacks?"

In Egypt, ever since the Nasserist era, keeping control over statistics has been treated as a matter of national security. The quaintly named Central Agency for Public Mobilisation and Statistics (or Capmas) was established by presidential decree in 1964 as the country's "official source for the collection of data and statistical information, and its preparation, processing and dissemination".

Capmas is in charge of "providing all the state bodies, organisations, universities, research centres and indevelopment [sic] and evaluation processes with the information that can help them to make informed decisions".

In effect, this gives the Egyptian state a monopoly on statistics, and for 30 years (at least) Capmas has been headed not by professional statisticians but by a succession of major-generals from the military.

Anyone wishing to compile data independently, through surveys or interviews, must first obtain a permit from Capmas's "General Department for Security" – and that even applies to university students.

Where controversial issues are involved, the security department often delays permission indefinitely or refuses it outright, without giving reasons. Capmas may also delete certain questions from a survey or demand that they be re-worded.

For countries that wish to survive and prosper in the modern world, this sort of attitude obviously cannot continue. But overcoming the fear of statistics requires a degree of openness that the Egyptian regime and many others are still reluctant to embrace. It's not just the numbers that they fear but the loss of control.