Against the background of unprecedented increases in world fuel prices leading to record increases in wholesale and retail gas and electricity prices so that a typical household's energy bills more than doubled since early 2004 Ofgem undertook the Energy Supply Probe. The numbers of consumers in debt to their energy suppliers, average debt levels and disconnection rates were all rising. These energy price rises came at a time when household budgets were under pressure from the rising cost of food, petrol, mortgages and other essentials. Vulnerable consumers and those in fuel poverty were particularly affected. The Energy Supply Probe published the findings on the operation of the UK retail energy markets and set out a package of measures to tackle the issues raised.