Add a unit driver to a table in a model

Applies to: TBM Studio 12.0 and later

There are two ways to add value to a table in a model:

Use a value column in the table. This is known as a unit driver. Unit drivers most often are used at the lowest tier in a model.
Allocate value to the table from another table. This is known as an allocation. Allocations most often are used to flow value from one tier in a model to another.

In the following image, the Cost Source Actuals table has two-unit drivers: OpEx Variable and OpEx Fixed.

The information below describes how to add a unit driver. For information on allocations, see Create an allocation.

To add a unit driver to a table:

Click the table in Project Explorer and check out the table.
Add a Model step.
Click the Model step.
In the Model workspace, click Add Unit Driver under the Drivers column.
Under Add To, click the metrics to which the driver will apply.
Under Using, click the driver type (see below for an explanation of the driver types).
Complete the driver's definition based on the driver's type you selected:
- Column: select a column
- Metric: select a metric
- Formula: enter a formula

Optionally, under Notes, enter information about the driver.

The Source and Destination tabs in the table on the right side of the dialog show row by row how the value is being distributed.

Driver types

There are three types of drivers.

Column - The value is taken from a column in the table. This is the most common type of driver.
Metric - The value is taken from another model metric.
Formula - An equation generates the value. The equation can include values from the table or other tables.