Construction & Materials

Fuel Adjustment Worksheet

Fuel Adjustment for Earthwork Items

The specification for Fuel Adjustment, Section 2120 of the Standard Specifications, applies to an item when the contract quantity of the item is 50,000 CY or more. 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

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 Office of Construction and Materials 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.

  1. Complete contract information in header of spreadsheet.
  2. 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)
  3. Enter the BPI in the designated space (Cell N6).
  4. 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.
  5. Obtain the Current Price Index (CPI) for a month from the Office of Contracts website
  6. Enter the CPI in the column “CPI” for the designated month.
  7. 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 E35 and Class 10 Excavation quantity in Cell F35. The total quantity for the month will be automatically computed and shown in the column labeled “Total CY”.
  8. 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.
  9. The fuel adjustment amount for the month will be automatically computed and shown in the column “NFA” (Net Fuel Adjustment) or “FA” (Fuel Adjustment).
  10. 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.
  11. The Contractor and Project Engineer shall agree upon the frequency of payment or credit.

For assistance, contact the Project Engineer or the Office of Construction and Materials (515-239-1280)


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