Weighted Moving Average

Weighted moving averages are difficult to construct but more reliable than the simple moving averages, where the average has a tendency to "bark twice": once at the start of the moving average period and again at the end of the period.

S&P500 with Weighted Moving Average

Weighted Moving Average Formula

A Weighted moving average (WMA) attaches greater weight to the most recent data. The weighting is calculated from the sum of days.

Example: For a 5-day weighted moving average the Sum of Days is 1+2+3+4+5 = 15
The weighting is shown below:

Day 1 2 3 4 5
Price ($) 16 17 17 10 17
Weighting 1/15 2/15 3/15 4/15 5/15
Weighted value 1.07 2.27 3.40 2.67 5.67
5 Day WMA         15.07

Weighted values are calculated by multiplying today's price by 5/15, yesterday by 4/15, and so on. The weighted moving average is the sum of the 5 weighted values.