Data Quality and Verification Office of Highway Policy Information Federal Highway Administration

Why Verify Verification versus Reviews MF reviews look at process Verification looks at specific numbers Old system is hand-entry of the data Nobody’s perfect Motor Fuels team checks and re- checks Errors still possible

Correspondence Verification memo Dated: Response due April 15 Virtually assured data will change Second round If no changes in the first round – FYI If changes in the first round – re-check

How to evaluate Compare State 551M monthly to the MF- 33GA (gas and gasohol) and the MF-33SF (diesel and other special fuels) Sum all the months in the year and check against the MF-21 Gasoline Total Consumption column Special Fuel Private and Commercial Highway Use column Note – there are reasons these don’t always match

Table MF-21- Motor Fuel Use Summary of the FHWA annual analysis Draft attribution data Available for review and correction Becomes the MF-27 (finalized) As MF-27, used to attribute federal highway revenue to the States

MF-21: A Closer Look - I Starting point: two-thirds over from the left Special fuels column Data taken from State data Removed all non-highway gallons That’s it for special fuels Gasoline Remember: gasoline/gasohol combined Start at column Total Consumption: agrees with total on MF-33GA

MF-21: A Closer Look - II Next column to the left: Losses Depends on State legislation None Flat percent losses Actual losses Complicated combinations Limited to one percent of total consumption plus actual losses New procedures in place

MF-21: A Closer Look - III Non-highway Use Two non-highway types Private and Commercial Public Two treatments P&C either State or model data Public is all model results Breakdown by P&C type in Table MF- 24

MF-21: A Closer Look - IV Public on-highway use Two types Federal civilian use State, County, Municipal, and Native American government use All data generated from FHWA models Note: Total Highway Use column is combined gasoline\gasohol used in attribution

Summary Verification: Is different than Process Review Final State data for attribution Should not substitute for checking the data Month-by-month With future techniques

Modeling Data Why FHWA models data Consistency among States Data not otherwise available Model off-highway gasoline P&C gasoline off-highway Public gasoline off-highway Relatively small impact

Modeling Data Gasohol Model Relatively large impact Why an issue Federal/State definition differences States don’t report by federal definition Attribution impact Federal revenue Incentives

Modeling Gasohol How the current model works IRS reports total gasohol revenue States providing reasonably good gasohol data are allocated their share of gallons derived from IRS data States with no gasohol are allocated zero gallons of gasohol States not in either of these categories are allocated the remaining gallons derived from

Modeling Gasohol Regression analysis Dependent variable: number of ethanol gallons consumed Independent variables: Ethanol plant proximity Producer’s incentive amount VMT in State non-attainment areas proportionate to State VMT Blender’s incentive amount Total gasoline consumed in the State

Modeling Gasohol Sum the estimated amounts derived from the regression calculation Derive each estimated amount’s percentage of the total estimated Multiply these percentages by the IRS remaining control total Derive the distribution for each State’s three levels of gasohol

Modeling Gasohol Model issues Over emphasizes proximity to gasohol production Conversion from MTBE to ethanol will spread gasohol use Model needs improvements

Modeling Gasohol Summary Significant impacts State data necessary but not sufficient Needs improvements before re- authorization