# Weighted Moving Average Calculator

Given a list of sequential data, you can construct the *n*-point weighted moving average (or weighted rolling average) by finding the weighted average of each set of *n* consecutive points. For example, suppose you have the ordered data set

10, 11, 15, 16, 14, 12, 10, 11,

and the weighting vector is [1, 2, 5], where 1 is applied to the oldest term, 2 is applied to the middle term, and 5 is applied to the most recent term. Then the weighted 3-point moving average is

13.375, 15.125, 14.625, 13, 11, 10.875

Weighted moving averages are used to "smooth" sequential data while giving more significance to certain terms. Some weighted averages place more value on central terms, while others favor more recent terms.

Stock analysts often use a linearly weighted *n*-point moving average in which the weighting vector is [1, 2, ..., *n-1*, *n*]. You can use the calculator below to compute the rolling weighted average of a data set with a given vector of weights. (For the calculator, enter weights as a comma-separated list of numbers without the [ and ] brackets.)

#### Number of Terms in a Weighted *n*-Point Moving Average

If the number of terms in the original set is *d*and the number of terms used in each average is

*n*(i.e, the length of the weight vector is

*n*), then the number of terms in the moving average sequence will be

d - n + 1.

For example, if you have a sequence of 120 stock prices and take a 21-day weighted rolling average of the prices, then the weighted rolling average sequence will have 120 - 21 + 1 = 100 data points.

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