Calculation Formula and Example
When the system performs a cost projection calculation, it uses a standard formula.
Percent Complete = (Actual Units ÷ Estimated Units) x 100
Projected Final = (Actual ÷ Percent Complete) x 100
In the JC Original Estimates form, you set up an estimate for a Concrete Form Work phase for your Labor cost type as 5,000 CY (cubic yards) with a cost of $8,000. You then post work progress in JC Progress Entry totaling 2,500 CYs, and have posted actual costs to date of $6,000.
Next, you initialize projections for the job. You find that the system has calculated the phase/cost type's Projected Final cost to be $12,000 ($4,000 over the original estimate) by assuming that if $6,000 is spent and the phase is 50% done, then it will take $12,000 to complete the job.
- (2500 ÷ 5000) x 100 = 50 (% complete)
- (6,000 ÷ 50) x 100 = 12,000 (projected final cost)
You can now evaluate the projection and if needed, revise (plug) the projected Final for units, hours, cost, and unit cost, as well as units/hour, hours/unit, man days, or cost/hour (depending on the option selected in the last line of the JC Cost Projections entry grid). You can also adjust the projected Final amount by changing the % Complete, Over/Under, or Remaining values for any of the projection lines.
Using projection calculations above, you decide that since you have developed ways to compensate for early high costs, you want to project that the labor on this phase will only overrun the estimate by $2,000 (rather than $4,000). To do this, you will override (plug) the projected cost figure to show $10,000 on the Cost Projections screen. This would recalculate to show the Projected Final as $10,000, the Remaining as 4,000, and the % Complete on cost as 60%.