By Tompion's death, in 1713, daily variation was less than a minute, and by the late 19th century, marine chronometers were accurate to fractions of a second per day.

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The National Statistics figures also showed there was a daily variation, something which has been seen since the 1970s, with more children born on weekdays compared to weekends and bank holidays.

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Third, the child with bipolar disorder often has a daily variation: he becomes highly active at night and in the morning he is like a hibernating bear, all but impossible to get out of bed.

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Apart from the starting collateral there is something called variation margin, adjusted daily.

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One of the highlights of working for a publication such as Springwise is the sheer breadth and variation of the ideas that we are exposed to on a daily basis.

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