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Construction & Materials

Fuel Adjustment Worksheet

Fuel Adjustment for Earthwork Items


The specification for Fuel Adjustment, Section 2120 of the Standard Specifications, provides when fuel adjustment applies to a contract or item. All categories (i.e. Roadway & Borrow, Unsuitable, Waste, Channel, Contractor furnished, etc.) of the following items are eligible for fuel adjustment:
  • Class 10, 12 and 13 excavation
  • Select backfill and treatment
  • Topsoil
  • Embankment-in-place
The Current Price Index (CPI) will be available at the Office of Contracts' website. The list provides CPI’s for past years. The Base Price Index (BPI) for fuel adjustment calculations will be the CPI listed for the month prior to the letting date of the contract.

Fuel Adjustment Calculation

The following provides information on fuel adjustment calculation for the below scenarios:

  1. Contracts where the DOT is the Contracting Authority
    • Using AASHTOWare Project*
    • NOT using AASHTOWare project
  2. Contracts where the DOT is NOT the Contracting Authority
    • Let on or after 4/16/24
    • Let prior to 4/16/24

*Note:  This would be DOT contracts beginning with the January 17, 2024 letting (the letting where full AASHTOWare Project implementation started) or prior to this, select DOT contracts that have the Developmental Specification “Fuel Adjustment for AASHTOWare Project” applied.

For Scenario 1a - Contracts where the DOT is the Contracting Authority and using AASHTOWare Project

There is no contract quantity threshold for fuel adjustment to apply to an eligible item.  This means that all eligible items of any quantities will have fuel adjustment calculated in AASHTOWare Project.

In accordance with Article 2120.05, fuel adjustment is processed automatically in each pay estimate for the quantity that is posted to the eligible item(s).  This means there is no need to use the fuel adjustment spreadsheet for calculations, because the AASHTOWare Project software handles the calculations.  Therefore, it is important that quantities for eligible items are posted on a Daily Work Report that is dated in the month that the grading work was performed.

For Scenario 1b - Contracts where the DOT is the Contracting Authority and NOT using AASHTOWare Project

Fuel adjustment applies to an item when the contract quantity of the item is 50,000 CY or more.

In accordance with Article 2120.04, the contractor shall provide to the Engineer, on a monthly basis, a spreadsheet with quantities and the calculated amount of fuel adjustment for the month. Payment will be processed with a Contract Modification.

A standardized Fuel Adjustment spreadsheet has been developed by the Construction and Materials Bureau and is available in EXCEL format.
Fuel adjustment will be made for items of work covered in Section 2120 when the CPI for the month the work is performed is more than $0.15 per gallon different than the BPI established at the beginning of the project.

For Scenario 2a -  Contracts where the DOT is NOT the Contracting Authority that are let on or after 4/16/24

Fuel adjustment applies to an item when the contract quantity of the item is 50,000 CY or more.

In accordance with Article 2120.04, the contractor shall provide to the Engineer, on a monthly basis, a spreadsheet with quantities and the calculated amount of fuel adjustment for the month. Payment will be processed with a Contract Modification.

A standardized Fuel Adjustment spreadsheet has been developed by the Construction and Materials Bureau and is available in EXCEL format.

Fuel adjustment will be made for items of work covered in Section 2120 when the CPI for the month the work is performed is more than 5% different than the BPI established at the beginning of the project.

For Scenario 2b - Contracts where the DOT is NOT the Contracting Authority that are let BEFORE 4/16/24

Fuel adjustment applies to an item when the contract quantity of the item is 50,000 CY or more.

In accordance with Article 2120.04, the contractor shall provide to the Engineer, on a monthly basis, a spreadsheet with quantities and the calculated amount of fuel adjustment for the month. Payment will be processed with a Contract Modification.

A standardized Fuel Adjustment spreadsheet has been developed by the Construction and Materials Bureau and is available in EXCEL format.

Fuel adjustment will be made for items of work covered in Section 2120 when the CPI for the month the work is performed is more than $0.15 per gallon different than the BPI established at the beginning of the project.

Instructions for Fuel Adjustment Calculation Spreadsheet

Download the E105 spreadsheet and save file to user's computer.

  • Scenario 1b - Contracts where the DOT is the Contracting Authority & NOT using AASHTOWare Project: Use tab "Prior to 4-16-24 letting"
  • Scenario 2a - Contracts where the DOT is NOT the Contracting Authority that are let ON OR AFTER 4/16/24: Use tab "NONDOT starting 4-16-24 letting"
  • Scenario 2b - Contracts where the DOT is NOT the Contracting Authority that are let BEFORE 4/16/24: Use tab "Prior to 4-16-24 letting"

  1. Check that correct spreadsheet tab is used (see above scenarios and corresponding spreadsheet tab).
  2. Complete contract information in header of spreadsheet.
  3. Obtain BPI, from the Office of Contracts website by selecting Price Index for month previous to month of the letting. (For example: Letting Date is October 18, select CPI for September)
  4. Enter the BPI in the designated space (Cell M7).
  5. Enter the contract quantity of the items in the designated rows in the “Estimated Project Quantities”. Other items included in the contract, but not listed, shall be added.
  6. Obtain the Current Price Index (CPI) for a month from the Office of Contracts website
  7. Enter the CPI in the column “CPI” for the designated month.
  8. Enter the quantities that have been hauled in the appropriate item columns and month row. For example, Selected Backfill and Class 10 Excavation were hauled in June. In the June row, the Selected Backfill quantity is entered in Cell E37 and Class 10 Excavation quantity in Cell F37. The total quantity for the month will be automatically computed and shown in the column labeled “Total CY”.
  9. When adding an item not already shown in the spreadsheet, use one of the columns designated for the applicable Fuel Usage Factor (FUF). The spreadsheet uses yellow shading for items which use a FUF of 0.20 and green shading for Embankment-in-Place items which use a FUF of 0.27.
  10. The fuel adjustment amount for the month will be automatically computed and shown in the column “NFA” (Net Fuel Adjustment) or “FA” (Fuel Adjustment).
  11. Submit a copy of the completed form to the Project Engineer. Payment or credit will be made by processing a Contract Modification. The form shall be completed and submitted on a monthly basis. The monthly quantities shall be added to the previous month’s spreadsheet.
  12. The Contractor and Project Engineer shall agree upon the frequency of payment or credit.


For assistance, contact the Project Engineer or the Construction and Materials Bureau (Earthworks Engineer: 515-239-1280)

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