Real-World Education for Modern Marketers

Join Over 350,000 Marketing Professionals

Start here!
Text:  A A
Forecasting Guide
Overview
Categories
Selecting the Approach
Combining Approaches
Judgmental Models
Delphi Method
Curve Fitting
Analogous Data
Time Series Models
Moving Average
Exponential Smoothing
Decomposition Models
Box-Jenkins Models
Regression
Leading Indicator
Input-Output Models
TECHNIQUE #5: Moving Average

BASIC IDEA: Data from a number of consecutive past periods can be combined to provide a reasonable forecast for next period. The greater the number of previous periods used, the more "smoothing" takes place.

PROCEDURE: To forecast next period's sales using a simple moving average, use the following procedure: Compute,

Yt+1 = St + St-1 + St-2 + .....+ St-J
-------------------------------
N

where,

Yt+1 = Forecasted sales for next period

St = Current period sales

St-1 = Actual sales of previous period

St-2 = Actual sales two periods ago

St-J= Actual sales J periods ago

N = Number of time periods included

• Note that this forecast is simply an average of past values

Important considerations:

1. How many periods should be used?

• If overall pattern is one of regular growth or decline with few fluctuations, smaller number is usually better.

• If data have been very stable but interrupted by frequent random variations, larger number is best.

• In short, try various numbers and choose one that tends to give the best results (i.e. least forecast error).

2. If a trend is evident in the raw data, try a double moving average model to capture it:

• This is merely the moving average of a moving average! To calculate (using 3 periods), use the following formulas and plug in the appropriate values.

Yt' = St + St-1 + St-2
-------------------------
3

 

Yt'' = Y't + Y't-1 + Y't-2
-------------------------
3

then the forecast for next period is calculated as:

Yt+1'' = 3Y't - 2Y''t

 

COMMENTS:

• Fairly simple method

• Slow adjustment to changes in data pattern

• Assigns equal weight to each past observation

 


Sign up for MarketingProfs Today ... it's FREE!

Get our best marketing tips daily—just enter your email address below to subscribe!


Search over 4,000 MarketingProfs Resources!  

Subscribe Today

IT'S FREE! Become a member to get the tools and knowledge you need to market smarter.

we respect your privacy.

Stay connected!

Don't miss a bit of MarketingProfs ... join the 350,000 marketers following us.

Most Popular

MarketingProfs Today

Get new marketing updates delivered to your inbox! Sign up for MarketingProfs Today for FREE!


Get to the Po!nt Newsletters

Bite-sized topic-specific newsletters on B2B Marketing, Content Marketing, Email Marketing, Search Engine Marketing, Small Business, Social Media and more. Sign up for one, two or all...for FREE!


Subscribe Today



MarketingProfs uses single
sign-on with Facebook, Twitter, Google and others to make subscribing and signing in easier for you. That's it, and nothing more! Rest assured that MarketingProfs: Your data is secure with MarketingProfs SocialSafe!