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Electric power trading day
For trading purposes in designating hours traded, the 24-hour period beginning at midnight and ending the following midnight. Complexities exist in different markets around daylight savings adjustments to the 24-hour day and the UK’s Electricity Forward Agreement (EFA) calendar – where the trading day for UK power started and finished at 11:00pm, and months consisted of four-week blocks. In October 2014, the UK changed to the Gregorian calendar and legacy EFA contract positions are lapsing as time passes the delivery period.