Work on Allocation modelled permanent resources

Use this modelling type if you know the amount of work that is required to complete a task. Work is the amount of an item that must be used up for the task to be complete. A resource completing an amount of work also has a work rate. For example, you may know that a task involves installing 400 metres of cable and that the Engineer resource has a work rate of 40 metres of cable installed per day. So 1 Engineer could complete the task in 10 days, or 2 Engineers could complete it in 5 days.

Select Work On Allocation in the Modelling type field.
Select a Calculated Parameter and Balancing Parameter from the Parameters group. The calculated parameter is the information that you want Asta Powerproject to calculate; the balancing parameter is the information that you want Asta Powerproject to change automatically if the task duration is amended in the bar chart. Setting a balancing parameter of None creates a fixed resource allocation that does not change if the task duration changes.
Enter the amount of work to be completed in the Work field.
Enter the work rate of the resource in the Work Rate field.

In some circumstances, it can be more appropriate to record the work rate against each individual task rather than against different resources. For example, a 'Produce glass pane' task or a could have a particular work rate - perhaps set by the machinery that is used - regardless of the resource that is assigned to the task; or a steel fixer could work at a different rate depending on the thickness of the steel they are working with. To specify a default allocation rate against an individual task, enter it into the Default allocation rate field, in the 'Effort & Modelling' fields, on the Task tab of the Bar and Task Properties dialog. If you do this, the task's default allocation rate is applied to any permanent resource allocations that are assigned subsequently to the task, overriding the permanent resource's default work rate.
Select the rate type that you want to use (Units Per Time Unit or Time Units Per Unit) in the Rate Type field.
Enter the number of resources that you are allocating to the task in the Allocation field.
Enter the duration for which the resource works in the Duration field. One of the fields in the Work Based Data or Calculation groups is disabled, depending on the selected calculated parameter.

For example, if you model Tilers so that 3 Tilers have to lay 3000 tiles at a rate of 50 tiles per day, the allocation needs 60 working days of effort, but the duration of the allocation is 20 working days, as you have 3 Tilers allocated.

If you reduce the task duration from 20 days to 15 days, the resource allocation is adjusted according to the selected balancing parameter:

When Allocation is selected, the allocation of Tilers increases from 3 to 4 so that the same amount of work can be completed in the time available.
When Work Rate is selected, the work rate of the Tilers increases from 50 tiles laid per day to 66.67 tiles per day. The Tilers must work faster to complete the work in the time available.
When Work is selected, the amount of work to be completed decreases from 3000 to 2250 tiles. This is because the Tilers are working for three quarters of the original resource allocation duration so they can only complete three quarters of the work.