Provisional Estimates of FAF OD Freight Flows by Highway

1
Provisional Estimates of FAF O-D Freight Flows by
Highway

• Charlie Han
• MacroSys Research and Technology
• May 15, 2007

2
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

3
An updating approach
Growth in freight tonnage
Provisional estimate of new freight tonnage
Benchmark Year freight tonnage
Freight flow from one region to another
4
What do we want?

• Answer Freight flows by commodity and by FAF O-D
  regions

FAF Region
B
Commodity flows
A
C
5
Method for Domestic O-D Flows

• Estimation Steps
• Step 1 The growth in total domestic highway
  freight tonnage

National total without region and commodity
details
Total domestic highway freight tonnage of
benchmark year Growth rate of highway freight
calculated from ATAs trucking tonnage index
Step 2 Break total growth into growth by
commodity
Growth by commodity Total growth Shares of
commodities in Total Output ()
6
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)

? National tonnage of commodity X (?X)
Distribution Factor (DF)
B
? Regional flow of commodity X (?X, B-C)
A
C
7
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
?GDP B
Commodity X in Benchmark year (X, O-D)
GDP B
Growth in GDP
B
?GDP A
?GDP C
A
GDP A
GDP C
C
Economic Size in Benchmark year
8
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)

? National tonnage of commodity X (?X)
? Regional flow of commodity X (?X, B-C)
Distribution Factor (DF)
B
Regional flow of commodity X in benchmark year
(X, B-C)
A
C
9
Method for International O-D Flows
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)
Imports
Imports
Exports
Exports
Imports
Exports
Imports
Exports
Port 2
Port 3
?
Port 1
?
Port 4
Imports
Exports
E (A?P1) ?
I (P1?A) ?
Imports
Exports
Imports
Exports
B
A
C
10
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)

11
Method for International O-D Flows
For Port i, where ?E(Pi) gt 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) lt 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) lt 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)