You can’t failed to have encountered the brouhaha about protracted and maddening border control queues at UK airports. As we edge closer and closer to the Olympics, and an influx of tourists, the issue has been gathering pace.
At its core is data; in fact the whole story hinges on how the various parties in the debate including Immigration Minister Damian Green, count waiting times. It’s the perfect story to dissect to its numerical nuts and bolts.
I caught Radio 4’s More or Less programme (a must listen for data fiends) to try and make sense of the statistics.
And I should preface all this by saying that the target to process non-European passport holders is 45 minutes 95% of the time. It’s 25 minutes for European passport holders.
Wild exaggerated stats?
Last week Green told Parliament that the information had been wildly exaggerated and quoting “internal management information” (i.e. not official statistics), said the longest wait for non-EU nationals at Heathrow’s Terminal 5 was 90 minutes. Although he neglected to mention what timescale this longest wait relates.
CEO of the International Airlines Group Willie Walsh stated, in reaction, that Green himself was misinformed – and highlighted evidence of people queuing for over 2.5 hours.
It seems that Green’s figures came from the Border Agency but relate to a period last year and not to April. More or Less explained that the Border Agency collate data by choosing one person per hour from the back of the immigration queue, and then timing their progress.
The problem with this is that the influx of people isn’t steady; there are peaks and troughs in the numbers arriving at immigration. The Border Agency’s claim that 98% of non-EUs were channelled through checks in 45 minutes (last year – I have to point that out again) is based on biased data. It would be more accurate to choose one person per 1000 people passing through – rather than per hour – to measure its performance.
BAA’s data release
BAA’s more up-to-date but sketchy data on Heathrow was released shortly after the Green and Walsh bust-up and sheds new light on the debate.
It seems that BAA monitor queues in a pretty similar way to the Border Agency but select one person every 15 minutes so there’s potential to be slightly more accurate.
BAA was also able to specify exactly when Walsh’s 2.5 hours stat relates to (17 April, since you ask). It also plucked a three-hour wait out of its statistical arsenal (30 April).
Anyway, nitpicking aside, Heathrow’s performance was pretty shoddy over April. And as More or Less points out the targets are pretty lenient anyway – a 45-minute progress through immigration isn’t exactly speedy.
To listen to More or Less, click here