Air travel demand rose 2.4 percent year-on-year in January 2020, the lowest it has been since the April 2010 eruptions of Eyjafjallajökull, though travel disruptions due to coronavirus only began in late January. By March, the number of flights had plummeted, with about 280,000 flights reported between 24 and 30 March 2020 compared to around 780,000 in a similar period the previous year. Despite a lack of passengers, regulations regarding flight slots initially compelled British airlines to fly empty planes to European airports to avoid losing their slots. Fuel prices dropping (due to an oil price war between Russia and Saudi Arabia) by around a quarter could not compensate for the fall in demand. Google Trends indicate that airline customer service departments have received the largest rise in online searches between February and March 2020 than any other customer service department over that time period.