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End of day, end of business, close of business or COB is the end of the trading day in financial markets, the point when trading ceases. In some markets it is actually defined as the point in time a few minutes prior to the actual cessation of trading, when the regular traders' orders are no longer received. During this period, the market is performing what is called a "Run To Cash", which is when the market is reconciling to its underlying Cash Market. End of the day in the U.S. is usually at 4:00 pm.

In the United States military, end of day is the time when all scheduled training and administrative work stops. The unit's senior noncommissioned officer may hold a formation at this time. During this formation, guidance is given to the enlisted members, the unit commander may publish information and the unit is given the command fall out, which usually means done for the day. However, some members of the unit, especially maintenance crews, may continue working

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