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Pontifications on Poison

Being some ramblings on events associated with poisonous plants.

Thursday 24th January 2013

To those who think I’m becoming obsessed with Catha edulis, khat, I’d like to point out that this piece is not about that plant. It is about maths and reporting standards, especially about how reporting involving ‘drugs’ is always overblown. It does, though, use khat as the ideal example of what I mean.

It begins with a Channel 4 report1, ahead of the release of the ACMD report, that included the statement that the khat market in the UK is worth over £400m per annum. I did a quick calculation and couldn’t get anywhere near that figure. I tweeted that Channel 4 was playing ‘think of a number’ and heard back from the reporter that he had taken the figure from a report published by the London Borough of Hillingdon2.

I was aware of this 2011 report but hadn’t paid a lot of attention to it. I did refer to it when writing about Mark Lancaster’s adjournment debate in parliament. Thursday 12th January 2012 I said that one of his claims seemed to come from this report but ‘it hasn’t been possible to find any more detailed information’. At that time, I didn’t trouble to see if that was typical of the whole report.

A quick scan of it suggested that it was compiled from other reports and, since I prefer to go to primary sources, I didn’t read it thoroughly. But, after Jamal Osman, the Channel 4 reporter on the story, cited it as his source for the over £400 million figure, I thought I’d look at it more closely.

I won’t try and evaluate every number the report gives. But I’ll start with an easy one. Paragraph 4 says ‘…the Yemen where over 100,000 hectares of land are used for its cultivation’. It gives ‘Anderson. D, Beckerleg. S, Hailu. D, Klein. A, The Khat Controversy: Stimulating the Debate on Drugs, Berg Publishers; illustrated edition, (1 April 2007)’ as the source for that figure.  

I have that book so it was easy to see that what it actually says is;

‘According to Kennedy (1987), khat in the Yemeni economy contributed 50 per cent of agricultural output in 1973/74, from 43,000 hectares or 2.8% of the cultivated land. By 1987, the crop occupied about 5% of the arable land in Yemen.’

5% is just under twice 2.8% so what the source cited by the Hillingdon report actually says is that, ‘according to Kennedy’ khat cultivation covers less than 86,000 hectares in Yemen not ‘over 100,000’.

It is unnecessary to examine external references to challenge many of the numbers used by Hillingdon because the report contradicts itself repeatedly. Paragraph 8 says;

‘Once mature, the plants are cut by hand, made into bundles of 250 grams in weight and wrapped in banana leaves to maintain freshness. Up to 40 bundles are then placed in cardboard boxes for transportation.’

Paragraph 15 says;

‘The total annual imports of khat into the UK come from Kenya, Ethiopia, Yemen and Somalia via Kenya. An annual total of around 1,95million kgs/1,917 tons.’

And paragraph 16 says;

‘Each flight brings in over 36 tons of khat a week equating to seven tons per flight, there is one flight a day, five days a week. A total of 9,000 boxes or 1.8 million bundles each week being imported into the UK’

I set aside ‘Each flight brings in over 36 tons of khat a week’ as simply sloppy writing but you would think it would raise the eyebrows of any reader and make them aware of the possibility that this is not the highest quality piece. Instead, I looked at the internal consistency of the various figures given for the imports of khat.

250gm per bundle, 40 bundles per box is 10kg per box. 9,000 boxes a week is 90 tonnes not 36 tons[sic] so the number of boxes and the total weight of imports doesn’t agree.

1.8 million bundles at 40 to the box is 45,000 boxes not 9,000.

1.8 million bundles at 250gm per bundle is 450 tonnes per week not 36.

TTime to bring in the number of users but that gives another problem. Paragraph 19 says;

‘The main users of khat come from Somalia, Kenya, Ethiopia and Yemen. The most recent recorded data that is from the 2005 ACMD report. The number of users is estimated at 400,000 adult men and women, and young people’

But paragraph 20 says;

‘It was reported that an estimated 34 per cent of men are users (68,000) and an estimated 20 per cent of women are users (20,000). There are an estimated 88,000 users or consumers in the UK.’

Both 400,000 and 88,000 are supposed to come from the same ACMD report. That report3 does not contain the figures 400,000 or 68,000 or 20,000 or 88,000 and makes no estimate for total users from which those numbers might be derived.

So, we have a problem with number of users but let’s look at both estimates.

1.8 million bundles a week would give each of 400,000 users an average of 4.5 bundles to chew. That’s not impossible. For 88,000 users, however, the average is 20.5 bundles and would mean an average user chewing 3 bundles a day every day.

We can soon dismiss the 400,000 estimate. According to the 2001 census there were around 43,000 people of Somali ethnicity in the UK. Estimates suggest that number has risen to around 100,000. Of the three main khat chewing diasporas, Somalis are by far the greatest but even if we said the Ethiopian and Yemeni figures were the same we still get only 300,000 and, of course, not all of them chew khat.

It seems probable that the actual number of users is in a range that includes 88,000 so I’ll continue with that figure. 9,000 boxes gives 360,000 bundles a week or an average of 4 bundles per user. The latest ACMD report, see yesterday’s blog, suggests a ‘moderate’ consumer uses that level.

Next in the Hillingdon reports come the key figure, total market.
PParagraph 20 says;

‘Based upon the total street value of khat imported into the UK (£468 million), and with an estimated 88,000 consumers, the average expenditure on khat is circa £5,300 per user per annum’

You can look at that figure from several different points of view. £468 million is £9 million per week. Taking a range of £3-6 per bundle as the retail price that is somewhere between 1.5-3 million bundles per week; a range that includes the 1.8 million per week shown, above, to be nonsense.

£5,300 per user per annum gives a range of 880 to 1760 bundles or 17-34 per week not 4.

Let’s look at that £468 million one more way before dismissing it as complete nonsense.

PParagraph 18 of the Hillingdon report says;

‘The contribution made by khat to the Kenyan economy amounts to Kshs. 1,520,378,300. This equates to £12,669,819.16’

Not all Kenyan khat comes into the UK and not all khat that comes into the UK is Kenyan but it does make up the overwhelming majority. If we take £12 million as the FOB value of khat exports to the UK and add 20% for airfreight, we get £14.5 million. This would yield £3 million a year in VAT.

And that lines up with what the ACMD report says in paragraph 54;

‘The 2011/12 data confirms that khat had an import value of £13.8 million yielding taxation income of £2.8 million. Volume estimates are based on taxation raised and are reverse calculated. Based on these figures the volume of khat imported in this period was approximately 2,560 tonnes’

The total import cost, adding warehousing and transport to £14.5 + £3 million cannot possibly exceed £20 million so a £468 million annual market suggests a multiple of 23 times (I won’t give it as a percentage it just looks too silly.) The ACMD, when considering the involvement of organised crime or terrorism in the khat market noted that profit margins are very low.

Look at it by weight. 2,560 tonnes is, excluding packing weight, just over 10 million 250 gram bundles. If the retail price were all at £6 a bundle that is an annual market of £60 million. If every bundle weighed only 125gms and still sold for £6 you only get to £120 million.

To be clear, I don’t know what the total market for khat is. I’m suggesting it cannot possibly exceed £120 million. A figure of £468 million is, therefore, a complete nonsense.

Looking at the poor quality of the Hillingdon report, I’m not that upset with the council for putting ridiculous data into the public domain. I do though have to ask why such data gets repeated when it is so simple to identify its shortcomings.


1. Khat: a legal high, but should it be banned? Channel 4 22nd January 2013
2. The Hillingdon Khat Report: A call for action 26th May 2011 London Borough of Hillingdon
3. Khat (Qat): Assessment of Risk to the Individual and Communities in the UK. Advisory council on the Misuse of Drugs December 2005


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