The Timewise Analytics addon for Google Sheets ™ allows you to create, manipulate and chart timeseries directly in a Google Sheets ™ cell. There are over 40 functions available covering data processing, maths and statistics.

Stats
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Median
Variance
StandardDeviation
Skew
Kurtosis
Autocorrelation
Covariance
Correlation
Regression
PCA
Histogram

Moving Stats
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MovingAverage
MovingMin
MovingMax
MovingMedian
MovingVariance
MovingStandardDeviation

Math
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Add
Subtract
Multiply
Divide
Absolute

Charting
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Timeseries
Spread
Regression
Box Plot
Histogram
PCA