A relative strength database is defined as a collection of individual relative strength dates that have been generated using the same relative strength time period. For example, one relative strength database would be all the values you generated over a 250 day period, while another database would be all the values you generated over a 25 day period.
A delta relative strength database is defined as a collection of individual delta relative strength dates that have been generated using the same relative strength value and the same number of relative strength periods. For example, one delta relative strength database would be all the values you generated over a 250 day period using 4 relative strength periods, while another database would be all the values you generated over a 250 day period using 5 relative strength periods. These databases would be referred to as a 4-250 and a 5-250 database, respectively.
The following discussion applies to both the relative strength and delta relative strength databases; however, for simplicities sake, we will refer just to a relative strength database.
We strongly recommend generating the current relative strength values at the end of the trading week. The databases can become large and unwieldy if you generate these values on a daily basis, and in most cases, it is also unnecessary since the relative strength value of a particular financial instrument will not change that much on a daily basis.
You have to generate past relative strength values if you wish to use them in historical testing. We should warn you that a relative strength database can consume an enormous amount of disk space depending on the amount of financial instruments you include in the generation. We strongly recommend generating one year’s worth of relative strength values so you can see the amount of disk space a year takes.
We should also warn you that the database generation takes time. For example, it takes roughly 25 minutes to generate relative strength values for a particular date on 8000 financial instruments. With this in mind, we recommend creating a year’s worth of values at night after you won’t need your computer for other tasks. There is an option that allows you to create your entire relative strength database. Assuming again that you have 8000 financial instruments in your database and that you have 30 years of data for each instrument, it will take roughly three days to generate this database, so use this option wisely, as there are times during the database generation that you cannot cancel the operation.
It is important to remember that when you generate a particular relative strength database to make sure that you are generating it in the proper relative strength directory.