Output variable “ExtraVmtTax” is not affected by inputs

[JohnMillerVDOT]

In our dataset, the attribute RoadPresOpMaintCost.2005 had a value 0.01 meaning one cent (in 2005 dollars) per light-duty vehicle mile traveled. The attribute ArtLnMiCost.2005.1e3 had a value of 1800, meaning $1.8 million (in 2005 dollars) per lane-mile constructed. These attributes are found within the file region_road_cost.csv. When we then multiplied these attributes by 100, the output variable ExtraVmtTax which was found within the Region_2045.csv file was unaffected. To be clear, this increase in road maintenance costs did affect mode split: the 100-fold increase reduced VMT and vehicle trips by 84%, which seems to be a good logical result; the main concern here is the ExtraVmtTax attribute. This is discussed in the report https://www.virginiadot.org/vtrc/main/online_reports/pdf/22-R21.pdf on printed pages 45-46 under the heading “Changes in Roadway Maintenance and Construction Costs.”