Please note that because kidnapping is a criminal activity and because many kidnaps go unreported (it’s estimated that only one in ten are reported), there are few comprehensive studies from which to draw data. Add to this the fact that kidnapping reports are often collected under reviews of terrorism. For these reasons, the figures below should be treated as estimates.

• 8,000: the number of annual worldwide kidnappings.

• $5,000-100 million: the range of ransom demands.

• 3,000: the annual number of kidnappings in Mexico. Until recently, this made it second in the world for kidnappings. That position has now been taken by Iraq. (See the Interactive map to find out who is number one.)

• $500m: the annual global takings of the kidnap industry.

• 100%: the increase in kidnapping around the world in the last six years.

• 90% of kidnap victims are locals not foreigners. Roy Hallums may have been one of 400 foreigners kidnapped in Iraq but, in the same period, 30,000 Iraqis were kidnapped.

• 21%: the number of hostages in Latin America who survive rescue attempts.

• 40% of kidnap victims are released safely after payment of a ransom, according to Control Risks of London. Estimates, however, vary with one source stating that as many as nine out of ten are released.

• 11% of kidnap victims are released without a ransom being paid, either through negotiation or because the abductors realise that no-one’s going to pay up.

• 10: the average number of kidnappings daily in Columbia.

• 3% of kidnappers caught in Columbia are convicted compared with 95% in the US.

• 1 in 10: the ratio of kidnappings reported to the authorities.