The Folder Average Tool calculates the average open, high, low, and close of all securities in a folder. This is also known as a price-weighted index. The calculation is a simple summation of all values for each day, and then division by the number of securities for each day. Volume and Open Interest are summed up, not averaged. The Dow Jones Indices are price-weighted, although most others are capitalization-weighted. Higher-priced issues in a price-weighted index have a bigger influence on the index than lower-priced issues.

Load Info

Last Date - the last date of data to load.

Time Periods - the number of time periods to load. Data will be loaded even if a security doesn't have the specified time periods (e.g., if you specify 500 days, and a security has 400 days, it will still be loaded).

Require Data on Last Date - select this option to force the program to only load securities that have data on the last date specified. This assures that only securities that are trading as of the last date are included, and prevents any "old" securities from being included. Maybe you want those "old" securities, maybe you don't. It's up to you.

"Smart-Adjust" the Average - if you just do a straight average of every security in a folder, you'll get jumps up and down in the average as stocks come public, or stop trading, or don't trade for a day. If you select "Smart Adjust", the gaps created by such activity will be filled (e.g., if XYZ doesn't trade on May 2, the "Smart Adjust" would use the value from May 1).

MetaStock Folders - the calculation folders. An average is calculated for each folder.

Add - select this button to add a new folder (or folders if you select the "subfolders" checkbox) to your list of folders.

Subfolders - select this checkbox before pressing Add, and you'll be able to add all of the MetaStock folders below a given folder to your calculation (e.g., if you select "C:\MetaStock Data\Industry Groups", if will find every MetaStock folder below that folder and add it to the list).

Remove - select this to remove a folder from the calculation list.

Lists - once you've created a grouping of folders, you'll probably want to save it in a List so you can load it again later, or access it from another calculation tool.

Where's the data?

For maximum flexibility, the resulting calculations are put in two places:

First, the averages are saved as MetaStock files to a MetaStock folder of your choice (see Tools | SpyGlass Options to change the folder). This allows you to page through all of the resultant calculations.

Second, the averages can be retrieved by MetaStock using the "ExtFml( "Folder Average.GetValue", Folder, Field) " function. The "Folder" parameter is the name of the MetaStock folder upon which the average was calculated (e.g., "My Favorite Stocks"). The "Field" parameter is the price field to retrieve, either OPEN, HIGH, LOW, CLOSE, VOLUME, or OPENINT. This method allows you to use the calculations in explorations, custom formulas, experts, and system tests. The data itself is actually stored in an ASCII file in the same folder as the one specified for MetaStock files.