Demand forecasting for project resources

Demand forecasting in project management compares the hours a project portfolio needs with the people available to deliver them. Build the comparison by month and role, then attach the planned cost rates. The useful result is a list of specific resource gaps that project owners can resolve.

Begin with remaining work and a dated portfolio

Use the project workbook already maintained by delivery leaders. Keep one row per project, work package, role and delivery month, with required hours, approval status, forecast version and planned hourly cost. Use remaining work from the forecast date onward; adding the full original estimate to hours already completed overstates future demand.

Keep a separate capacity sheet with month, role, team, available delivery hours and cost rate. Available hours should exclude approved leave and the shared duties already allocated elsewhere. Identify people appearing on more than one team's roster before totaling capacity.

This is resource planning, rather than a project to develop a statistical forecasting method. The general demand forecasting guide covers predicting demand; this comparison starts from supplied project requirements and approved scenarios.

Work the resource and cost requirements

Required hours by role and month = Sum of project hours assigned to that role and month

Planned resource cost = Required hours × Planned hourly cost

Capacity gap = Required hours − Available hours

A US professional services company is reviewing November 2026 commitments. All four rows are approved remaining work for that month. Dollar amounts use USD; load percentages are rounded to one decimal place.

Name this sheet Plan. Put its columns in A:F, with the detail in rows 2:5. Store month keys in F as text, such as 2026-11. In Excel, enter this in E2 and fill down:

=C2*D2

Then calculate the cost independently:

=SUMPRODUCT(C2:C5,D2:D5)

Microsoft's SUMPRODUCT documentation describes multiplying corresponding ranges and summing their products. The result must match the 90,000 total in column E. Keep rates consistent: these are planned labor costs, rather than customer billing rates or recognized revenue.

For the remaining financial forecast, use project cost management alongside this resource view. External purchases and fixed fees need their own cost rows; they cannot be inferred from labor hours.

Compare each role with its available hours

The capacity owner supplies 400 analyst hours and 480 engineer hours for November. Applying the same cost rates gives the following comparison. Positive gaps mean shortages; negative gaps mean spare hours.

Build a separate summary sheet with role in A, required hours in B, available hours in C, gap in D and load in E. Use the Plan sheet's month in F, role in B and required hours in C. Required hours in summary cell B2 are:

=SUMIFS(Plan!C:C,Plan!F:F,"2026-11",Plan!B:B,A2)

Gap in D2 is =B2-C2; planned load in E2 is =B2/C2.

Microsoft documents SUMIFS for summing rows that meet multiple criteria. Here, both the month and role must match. Copy the formulas for each role and calculate total load as total required hours divided by total available hours, never the average of role percentages.

Covirage is not affiliated with Microsoft.

Prove the comparison before changing assignments

The requirement check is 440 + 420 = 860 hours, matching the project rows. Capacity is 400 + 480 = 880 hours. The role gaps reconcile: 40 − 60 = −20 hours, the same as 860 − 880.

The cost check reaches the same conclusion by role. Analyst requirements exceed the capacity allowance by 40 × $90 = $3,600. Engineer requirements are below it by 60 × $120 = $7,200. Net planned labor cost is $3,600 below the allowance: $90,000 − $93,600.

That apparent cost headroom does not solve the analyst shortage. Reassign work only when skills, access and project commitments permit it. If project owners approve moving 40 analyst hours into December, November analyst requirements become 400 hours and the November analyst shortage closes. Record those 40 hours in December's requirements before accepting the change.

The portfolio manager owns the overall demand view, project managers own remaining effort and dates, and team leads confirm available skills. Capture decisions in the project management report so a shifted deadline and the next forecast remain consistent.

Where resource forecasts go wrong

• Mixing total and remaining effort. Hours already delivered belong in actuals, not next month's requirement.
• Treating all spare hours as interchangeable. Available engineering time cannot cover analyst demand without a valid skills match.
• Counting a person twice. Shared staff need one capacity record and an explicit allocation across teams.
• Moving work out of the horizon. A delayed project reduces one month's requirement and increases a later month's. It does not remove the work or its cost.

Keep forecast versions dated. A current plan should inform assignments; a frozen earlier plan should measure how assumptions changed. The project cost control overview provides supporting context for reviewing the financial position alongside delivery requirements.

Compare your portfolio files in Covirage

Bring the project requirements, monthly capacity and planned rates: Covirage maps the columns, its tools compute and check the role, month and cost comparisons, and the external AI model explains the results with every figure traced to its rows. Create a free Covirage account, which takes about a minute, then set up your business and bring a sample of your own data.

See Covirage for professional services for the supporting industry context.