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Item 3. Version 2.3 Travel Model Update . Presentation to the Travel Forecasting Subcommittee Ron Milone and Mark Moran National Capital Region Transportation Planning Board September 19, 2008. tfs_Pres_Ver2.3_9_19_08_Final.ppt. Today’s Discussion. Recent updates to Version 2.3 model

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Version 2 3 travel model update l.jpg

Item 3.

Version 2.3 Travel Model Update

Presentation to the

Travel Forecasting Subcommittee

Ron Milone and Mark Moran

National Capital Region Transportation Planning Board

September 19, 2008

tfs_Pres_Ver2.3_9_19_08_Final.ppt


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Today’s Discussion

  • Recent updates to Version 2.3 model

  • Version 2.3 sensitivity testing

    • increased auto operating cost (2002)

    • two system alternatives (2005)

  • Proposed method for reflecting employer-based transit fare subsidies (i.e., SmartBenefits/Metrocheks/Farecards)

Ver. 2.3 Presentation to the TFS 9/19/2008


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Review of 2005 Trips Assigned

  • Observation: Even though V2.3 vehicle trips are higher than V2.2, the number and proportion of V2.3 intra-zonal trips is lower than V2.2, and the proportion of V2.3 trips loaded is higher than V2.2

  • Consequence: Increase in V2.3 trips results in higher-than-expected increase in trips loaded and in VMT

Ver. 2.3 Presentation to the TFS 9/19/2008


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Observed Data Sources Checked

  • Auto Person intra-zonal percentages

    • 1994 Household Travel Survey (for the 13 jurisdictions surveyed)

    • 2000 CTPP (modeled area)

  • Conclusion - Existing modeled intra-zonal percentages need adjustment

Ver. 2.3 Presentation to the TFS 9/19/2008


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Modeled Adjustments

  • Intra-zonal time assumption (used in trip distribution) modified

    • Was: 0.50 of minimum inter-zonal time

    • Now is: 0.85 of minimum inter-zonal time

  • Reduction in intra-zonal trips necessitated other changes

    • Non-work trip generation reduced by 15%

    • NL mode choice model re-estimated

  • Re-calibrated model performance acceptable

Ver. 2.3 Presentation to the TFS 9/19/2008


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Sensitivity test for 2002

  • Base

    • Assumed auto op. cost: 10cents/mi (’94$)

  • Test

    • Auto operating cost increased by 30% (i.e., set to 13 cents/mi)

Ver. 2.3 Presentation to the TFS 9/19/2008


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Cost of driving

  • Cost of driving vis-à-vis the mode choice model:

    • Includes: “Out-of-pocket” costs

      • Gasoline

      • Other maintenance costs, i.e., repairs, oil, tires, etc.

    • Excludes: “ownership” costs

      • Cost of purchasing the vehicle

      • Insurance

      • Vehicle registration

  • Assumption: When a traveler is choosing which mode to take, he/she incorporates only some of the costs, i.e., the “out-of-pocket” costs, not the long-term costs associated with owning a vehicle (which the traveler sees as sunk costs)

Ver. 2.3 Presentation to the TFS 9/19/2008


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Cost of driving

  • Four major factors that influence driving costs:

    • Price of gas

    • Price of maintenance and repairs

    • Vehicle fleet fuel economy

      • As the vehicle fleet becomes more fuel efficient, the cost of driving generally goes down

    • Vehicle fleet mix

      • The mix between cars and light-duty trucks (pickups, SUVs, minivans) affects average fuel economy

      • As the share of LD trucks goes up, fuel efficiency goes down, which increases the cost of driving

Ver. 2.3 Presentation to the TFS 9/19/2008


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How does model address auto operating costs?

  • The “cost of driving” is entered into the mode choice model as a per-mile, average auto operating cost

  • Version 2.3 travel model:

    • Assumes 10 cents/mile in constant/’94 dollars

  • There is no one parameter where one can specify the assumed price of gas.

    • One specifies the average auto operating cost, which implicitly includes the cost of gas and the other three factors (maintenance, fleet fuel economy, and fleet mix)

Ver. 2.3 Presentation to the TFS 9/19/2008


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Increase auto operating costs 30%

Ver. 2.3 Presentation to the TFS 9/19/2008


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Sensitivity Tests for 2005

  • Two system alternatives examined:

    • Removal of the Pennsylvania Ave. (John Phillip Sousa) Bridge (hypothetical)

    • Removal of two lanes from the American Legion Bridge, from 5 to 3 lanes in each direction (again, hypothetical)

Ver. 2.3 Presentation to the TFS 9/19/2008


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Regional 2005 VMT

Ver. 2.3 Presentation to the TFS 9/19/2008


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Regional 2005 Transit Trips

Ver. 2.3 Presentation to the TFS 9/19/2008


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Directional Link Level Comparison American Legion Bridge Base & Alt. Condition

Ver. 2.3 Presentation to the TFS 9/19/2008


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Change in AM Peak Period Volume when the John Phillip Sousa Bridge is Closed(Year 2005)

Legend:

Red = Decrease

Green = Increase

Tolerance: More than +/- 2000 Vehicles

Ver. 2.3 Presentation to the TFS 9/19/2008


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Change in AM Peak Period Volumewhen American Legion Bridge is reduced by two lanes (Year 2005)

Legend:

Red = Decrease

Green = Increase

Tolerance: More than +/- 700 Vehicles

Ver. 2.3 Presentation to the TFS 9/19/2008


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Conclusions on 2005 Sensitivity Tests

  • Global results are generally reasonable

  • Area-specific link volume changes are reasonable

  • Results are comparable to similar tests of the Version 2.2 model

Ver. 2.3 Presentation to the TFS 9/19/2008


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Reflecting Employer-Based Transit Fare Subsidies

  • TPB’s transit fare estimation process reflects WMATA policy

  • It’s clear that employer-based fare subsidies are pervasive

  • The degree of fare subsidies is beginning to be understood with newly collected data

Ver. 2.3 Presentation to the TFS 9/19/2008


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Rules of thumb andObserved fare elasticities

  • Simpson & Curtin formula (TRB 2004)

    • 10% increase in fare => 3.8% drop in ridership

    • Observed elasticities can vary widely

Ver. 2.3 Presentation to the TFS 9/19/2008


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WMATA Fares and Ridership

  • “Despite the fare increase in January, total rail ridership for the fiscal year ending in June was up almost 4 percent over the previous year, and total bus ridership rose about 1 percent.”

    - Washington Post (September 12, 2008)

    http://www.washingtonpost.com/wp-dyn/content/article/2008/09/11/AR2008091103237.html

  • Reasons: New Baseball Stadium, recent development around stations, & employer subsidies.

Ver. 2.3 Presentation to the TFS 9/19/2008


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2007 Metrorail SurveyIncludes Subsidy Question

  • Question M: Do you receive a monthly transit benefit (i.e., SmartBenefits, Metrocheks or Farecards) from your employer?

    • Yes, SmartBenefits

    • Yes, Metrocheks/Farecards

    • Do not receive benefits

Ver. 2.3 Presentation to the TFS 9/19/2008


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2007 Survey Results

  • 60% of Metrorail work trip passengers receive some type of employer subsidy

  • Stations with largest percentage of subsidized work attractions:

    • Smithsonian (84%)

    • Federal Triangle (79%)

    • Federal Center SW (79%)

    • Medical Center (79%)

    • Capitol Heights (77%)

    • L’Enfant Plaza (75%)

Ver. 2.3 Presentation to the TFS 9/19/2008


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Reflecting Fare Subsidies

  • Develop peak station-to-station Metrorail fare (as normally developed)

  • Formulate station-to-station subsidy probabilities (from Metrorail survey)

  • Convert monthly subsidies to per-trip subsidies (subsidies are directly related to fare levels)

  • Reduce average fare at station interchange level using subsidy probability and fare subsidy

    Adjusted Metrorail Fare =

    (%subsidized*((normal fare – subsidy)) + (%not subsidized* (Normal Fare))

Ver. 2.3 Presentation to the TFS 9/19/2008


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Conclusions

  • Sensitivity tests have begun, development continues on Version 2.3

  • Procedures to adjust Metrorail fares reflecting subsidies will be formalized

  • Transit fare sensitivity will be examined

Ver. 2.3 Presentation to the TFS 9/19/2008