# Provisional Estimates of FAF O-D Freight Flows by Highway Charlie Han MacroSys Research and Technology May 15, 2007.

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Provisional Estimates of FAF O-D Freight Flows by Highway Charlie Han MacroSys Research and Technology May 15, 2007

Objective Develop Provisional Estimates of FAF Origin- Destination Freight Flows by Highway Measurements: Tons and Value (\$) Commodity Detail: 2-digit SCTG level Types of Origins and Destinations -Domestic: FAF Regions -International: FAF Regions and Ports of Entry/Exit

Benchmark Year freight tonnage Growth in freight tonnage An “updating” approach Provisional estimate of new freight tonnage Freight flow from one region to another

What do we want? Answer: Freight flows by commodity and by FAF O-D regions A B C FAF Region Commodity flows

Method for Domestic O-D Flows Estimation Steps: Step 1: The growth in total domestic highway freight tonnage = Total domestic highway freight tonnage of benchmark year × Growth rate of highway freight calculated from ATA’s trucking tonnage index National total without region and commodity details Step 2: Break total growth into growth by commodity Growth by commodity = Total growth × Shares of commodities in Total Output (\$) National total with commodity details

Method for Domestic O-D Flows Estimation Steps: Step 3: Distributing national growth by commodity to FAF regions For Example:  X (B-C) =  X × DF (X, B-C) A B C ▲ National tonnage of commodity X ( ▲ X) Distribution Factor (DF) ▲ Regional flow of commodity X ( ▲ X, B-C)

Method for Domestic O-D Flows Estimation Steps: Step 3-1: Calculating distribution factor for each pair of FAF O-D regions and each commodity  Y (B-C) = (  GDP (B) +  GDP (C) ) / (GDP (B, 0) +GDP (C, 0) ) × X (B-C, 0) DF (X, B-C) =  Y (B-C) /  (  Y (A-B),  Y (A-C), ……,  Y (B-C) ) And,  ( DF (X, A-B), DF (X, A-C), ……, DF (X, B-C) ) = 1 A B C Economic Size in Benchmark year GDP A ▲GDP A Growth in GDP \$ GDP C ▲GDP C GDP B ▲GDP B Commodity X in Benchmark year (X, O-D)

Method for Domestic O-D Flows Estimation Steps: Step 4: Calculating provisional tonnage estimates Provisional Tonnage Estimate: X (B-C, t) = X ( B-C, 0) +  X (B-C) A B C ▲ Regional flow of commodity X ( ▲ X, B-C) Distribution Factor (DF) ▲ National tonnage of commodity X (▲X) Regional flow of commodity X in benchmark year (X, B-C)

Method for International O-D Flows A B C ImportsExports ImportsExports Port 1 Port 2Port 3 Port 4 Imports Exports Imports Exports I (A) + I (B) + I (C) = I (P1) + I (P2) + I (P3) + I (P4) E (A) + E (B) + E (C) = E (P1) + E (P2) + E (P3) + E (P4) I (P1  A) ? ? ? E (A  P1) ?

Method for International O-D Flows E (X, A  P1, t) = E (X, A, t) × S (P1, X, A, 0) Where, S (P1, X, A, 0) = E (X, A  P1, 0) / E (X, A, 0) S (P1, X, A, 0) + S (P2, X, A, 0) + S (P3, X, A, 0) + ……+ S (Pn, X, A, 0) = 1 For Commodity not in FAF benchmark year (0): E (X, A  P1, t) = E (X, A, t) × S (P1, A, 0) Where, S (P1, A, 0) = E (A  P1, 0) / E (A, 0) S (P1, A, 0) + S (P2, A, 0) + S (P3, A, 0) + ……+ S (Pn, A, 0) = 1 ? If  [  (E (X, A  P1, t), E (X, B  P1, t), E (X, C  P1, t) ), for all X ] = E (P1, t) If not:  E (P1) =  [  (E (X, A  P1, t), E (X, B  P1, t), E (X, C  P1, t) ), for all X ] - E (P1, t)

Method for International O-D Flows For Port i, where  E (Pi) > 0, R (Pi) = E (Pi, t) /  [  ( E (X, A  P1, t), E (X, B  P1, t), E (X, C  P1, t) ), for all X ] E' (X, A  Pi, t) = R (Pi) × E (X, A  Pi, t), Where R (Pi) < 1 Then,  [  ( E' (X, A  Pi, t), E' (X, B  Pi, t), E' (X, C  Pi, t) ), for all X ] = E (Pi, t) Since E (A) + E (B) + E (C) = E (P1) + E (P2) + E (P3) + E (P4)  (  E (P1),  E (P2),  E (P3),  E (P4) ) = 0 For Port j, where  E (Pj) < 0, U (Pj) =  E (Pj) /  (  E (Pj), for all j ) E' (X, A  Pj, t) =E (X, A  Pj, t) + U (Pj) ×  [ (1-R (Pi) )×E (X, A  Pi, t), for all i) ] Then,  [  ( E' (X, A  Pj, t), E' (X, B  Pj, t), E' (X, C  Pj, t) ), for all X ] = E (Pj, t)

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