This column can be added to plansheets to specify a ratio of GRPs in full-price units and half-price units, such as is typical for 30s and 15s.

 

Type in a percentage of weight going to full-price units, and the system will display that percentage and the remaining percentage which is to be computed at half-price. Example: enter 75, and the system shows the entry as 75:25. Costs can (as usual) be entered as either CPPs or CPMs. Computed cost totals and bottom-line CPPs and CPMs will reflect the unit mix.

 

Here's an example:

 

 

 

This plan places 100 points on one vehicle.  The Unit Mix setting says that 75% of that weight is placed in units at full price, a CPP of $2,000.  The remaining 25% is placed at half that stated price.  The total cost is then computed:

 

 

 

Does the Length of a Commercial Affect Reach?

 

In general, the length of the unit has no effect at all on reach.  We either count a person as reached by a spot or not; it doesn't matter how long the spot is.

 

Of course, 30s can be expected to have more impact or effectiveness than 15s.  But that's not a reach question.  Reach is all about delivering an ad to a person.  How well the ad performs when it gets there is a different question!

 

Having said all that, there is the matter of cost.  If we have a campaign of 30s, and we use the same budget and instead buy all 15s at half the unit cost, we have just doubled the number of spots and double the GRPs.  And that will increase the reach!