trendline

or trend line

[ trend-lahyn ]
/ ˈtrɛndˌlaɪn /
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noun

an upward or downward line on a chart indicating movements of average prices, as of stocks, over a period of time.

Origin of trendline

1910–15 for more general sense; trend + line1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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