1. Gini Coefficient for the ten largest airports
of North America in passenger traffic for
2000 and 2011
Transportation and Sustainability-Geography 465
University of Illinois at Urbana-Champaign
Zaheeda Darvesh

2. 2 GINI Coefficients for Passenger Traffic in North America
PERCENTAGE OF AIRPORTS
X Axis
YAxis
PERCENTAGEOFPASSENGERS
LINE
OF
EQUALITY
(45
DEGREES)
GINI CONCENTRATION RATIO
0.14942 FOR 2011
GINI CONCENTRATION RATIO
0.17377 FOR 2000
Gini=1
Gini=0
Figure 1: Gini coefficient for passenger traffic in North America 2000 and 2011
Objective:
To compute the Gini Coefficient for passenger traffic of top ten airports in North America for 2000
and 2011
Methodology:
Passenger traffic for top ten airports in North America for the years 2000 and 2011 was collected
from the Airports Council International database (See Table 1 and 2).
This information can be accessed at
www.aci.aero/Data-Centre/Annual-Traffic-Data/Passengers/2011-final and
www.aci.aero/Data-Centre/Annual-Traffic-Data/Passengers/2000-final.
This information was then entered in the Gini Coefficient excel sheet to derive the Gini coefficients
for the two time periods (Table 3 and 4). The passenger traffic for 2000 reflects a Gini coefficient
of 0.17377, whereas the passenger traffic for 2011 reflects a Gini coefficient of 0.14942. The
larger Gini coefficient 0.17 (Figure 1), indicates greater concentration in fewer places, compared
to the smaller Gini coefficient 0.14 (Figure 1) which indicates more equal distribution of airports.
Based on this information, it can be inferred that compared to 2000, passenger traffic in 2011 is
more distributed. This could be due to emergence of other airports in the region highlighting the
changing structure of air transport networks wherein the development of hubs involves less direct
connections. Passenger traffic has also increased from 2000 to 2011, in line with the growing
population and their surging travel demands. The development of passenger services also induces
freight demand since each additional plane offers cargo capacity, which is made available on the
market.

3. GINI Coefficients for Passenger Traffic in North America 3
gini coefficient
World
Rank
in 2000
North
America
Ranking
Airport Location
Total
Passengers
1 1 ATLANTA GA, US (ATL) 80,162,407
2 2 CHICAGO IL, US (ORD) 72,144,244
3 3 LOS ANGELES CA, US (LAX) 66,424,767
5 4 DALLAS/FORT WORTH TX, US (DFW) 60,687,122
9 5 SAN FRANCISCO CA, US (SFO) 41,040,995
11 6 DENVER CO, US (DEN) 38,751,687
12 7 LAS VEGAS NV, US (LAS) 36,865,866
13 8 MINNEAPOLIS MN, US (MSP) 36,751,632
15 9 PHOENIX AZ, US (PHX) 36,040,469
16 10 DETROIT MI, US (DTW) 35,535,080
Table 1: Top 10 airports with most passenger traffic in North America - 2000
Source: Airports Council International Annual World Airport Traffic Report-2000
Accessed at http://www.aci.aero/Data-Centre/Annual-Traffic-Data/Passengers/2000-final
World
Rank
in 2011
North
America
Ranking
Airport Location
Passengers
2011
1 1 ATLANTA GA, US (ATL) 92,365,860
4 2 CHICAGO IL, US (ORD) 66,561,023
6 3 LOS ANGELES CA, US (LAX) 61,848,449
8 4 DALLAS/FORT WORTH TX, US (DFW) 57,806,152
11 5 DENVER CO, US (DEN) 52,699,298
17 6 NEW YORK NY, US (JFK) 47,854,283
20 7 LAS VEGAS NV, US (LAS) 41,479,572
22 8 SAN FRANCISCO CA, US (SFO) 40,907,389
23 9 PHOENIX AZ, US (PHX) 40,565,677
24 10 HOUSTON TX, US (IAH) 40,170,844
Table 2: Top 10 airports with most passenger traffic in North America - 2011
Source: Airports Council International Annual World Airport Traffic Report-2011
Accessed at http://www.aci.aero/Data-Centre/Annual-Traffic-Data/Passengers/2011-final
Note: Passenger Traffic, Total passengers enplaned and deplaned, passengers in transit counted once

4. 4 GINI Coefficients for Passenger Traffic in North America
Table 3: Ten Largest Airports of North America with passenger enplanement, deplanement and
transit numbers - 2000
Source: Airports Council International, Passenger Traffic 2000 FINAL
TEU
% of TEU
(Y)
% of
ports
(X)
σYi-1 +
σYi (A)
σXi-1 –
σXi (B)
A*B
ATLANTA GA, US (ATL) 80,162,407 0.15892 0.1 0.15892 0.1 0.15892 0.10000 0.01589
CHICAGO IL, US (ORD) 72,144,244 0.14303 0.1 0.30195 0.2 0.46088 0.10000 0.04609
LOS ANGELES CA, US (LAX) 66,424,767 0.13169 0.1 0.43364 0.3 0.73560 0.10000 0.07356
DALLAS/FORT WORTH TX, US (DFW) 60,687,122 0.12031 0.1 0.55396 0.4 0.98760 0.10000 0.09876
SAN FRANCISCO CA, US (SFO) 41,040,995 0.08137 0.1 0.63532 0.5 1.18928 0.10000 0.11893
DENVER CO, US (DEN) 38,751,687 0.07683 0.1 0.71215 0.6 1.34747 0.10000 0.13475
LAS VEGAS NV, US (LAS) 36,865,866 0.07309 0.1 0.78524 0.7 1.49739 0.10000 0.14974
MINNEAPOLIS/ST PAUL (MSP) 36,751,632 0.07286 0.1 0.85810 0.8 1.64334 0.10000 0.16433
PHOENIX (PHX) 36,040,469 0.07145 0.1 0.92955 0.9 1.78765 0.10000 0.17876
DETROIT (DTW) 35,535,080 0.07045 0.1 1.00000 1 1.92955 0.10000 0.19296
504,404,269 1 1 1.17377
Gini's Concentration Ratio 0.17377 G = |1-J13|
Table 4: Ten Largest Airports of North America with passenger enplanement, deplanement and
transit numbers - 2011
TEU
% of TEU
(Y)
% of
ports
(X)
Cumulative
% of TEUs
(σY)
Cumulative
% of ports
(σX)
σYi-1 +
σYi (A)
σXi-1 –
σXi (B)
A*B
ATLANTA GA, US (ATL) 92,365,860 0.17034 0.1 0.17034 0.1 0.17034 0.10000 0.01703
CHICAGO IL, US (ORD) 66,561,023 0.12275 0.1 0.29308 0.2 0.46342 0.10000 0.04634
LOS ANGELES CA, US (LAX) 61,848,449 0.11406 0.1 0.40714 0.3 0.70022 0.10000 0.07002
DALLAS/FORT WORTH TX, US (DFW) 57,806,152 0.10660 0.1 0.51374 0.4 0.92088 0.10000 0.09209
DENVER CO, US (DEN) 52,699,298 0.09718 0.1 0.61093 0.5 1.12467 0.10000 0.11247
NEW YORK NY, US (JFK) 47,854,283 0.08825 0.1 0.69918 0.6 1.31011 0.10000 0.13101
LAS VEGAS NV, US (LAS) 41,479,572 0.07649 0.1 0.77567 0.7 1.47485 0.10000 0.14748
SAN FRANCISCO CA, US (SFO) 40,907,389 0.07544 0.1 0.85111 0.8 1.62678 0.10000 0.16268
PHOENIX AZ, US (PHX) 40,565,677 0.07481 0.1 0.92592 0.9 1.77703 0.10000 0.17770
HOUSTON TX, US (IAH) 40,170,844 0.07408 0.1 1.00000 1 1.92592 0.10000 0.19259
542,258,547 1 1 1.14942
Gini's Concentration Ratio 0.14942 G = |1-J30|
Source: Airports Council International, Passenger Traffic 2011 FINAL
Note: Passenger Traffic, Total passengers enplaned and deplaned, passengers in transit counted once

5. GINI Coefficients for Passenger Traffic in North America 5
gini coefficient
Figure 2: Passenger traffic for airports in North America 2000-2011
Source: Airports Council International Annual World Airport Traffic Report-2000 and 2011
0 40,000,000 80,000,000
ATLANTA GA, US (ATL)
CHICAGO IL, US (ORD)
LOS ANGELES CA, US (LAX)
DALLAS/FORT WORTH TX, US (DFW)
SAN FRANCISCO CA, US (SFO)
DENVER CO, US (DEN)
LAS VEGAS NV, US (LAS)
MINNEAPOLIS/ST PAUL (MSP)
PHOENIX (PHX)
DETROIT (DTW)
NEW YORK NY, US (JFK)
HOUSTON TX, US (IAH)
Passenger Traffic 2011 Passenger Traffic 2000
Figure 2 shows that Detroit, Minneapolis, Dallas/ Fort Worth, Los Angeles and Chicago in the
U.S. have experienced decreased passenger traffic from 2000-2011. These airports might still be
counted as North America’s top 10 airports with larger passenger traffic, but over the decade,
the passenger traffic has decreased which could be factored to emergence of other airports in the
region such as the ones in Charlotte(NC), Orlando(FL), Newark (NJ), and others.
The North American passenger air transport system is designed around the hub-and-spoke
network structure. The activity level of passenger airports is related to the distribution of
the population with airports having a higher activity level either because they are the hubs of
major airlines or are important resort areas (e.g. Las Vegas, Orlando). For instance, Delta mainly
operates hubs at Atlanta (ATL), Detroit (DTW) and Minneapolis (MSP), while United mainly
operates hubs at Denver (DEN), Houston (IAH), Chicago (ORD), Los Angeles (LAX) and Newark
(EWR). American Airlines mostly operates hubs at Dallas-Fort Worth (DFW), Chicago (ORD) and
Miami (MIA) Figure 2. Hence, these airports are associated with increased passenger air traffic
due to its designation as important points of interchange.
Delta Airlines
Delta Airlines
Delta Airlines
United
United Airlines
United/ American
Airlines
United Airlines
American Airlines
Delta/ American
Airlines
United Airlines
Allegiant/ South
West Airlines
Major carriers

6. 6 GINI Coefficients for Passenger Traffic in North America
Observation:
The Gini coefficient for passenger traffic for airports in North America in 2000 was 0.17, while1.
that for 2011 was 0.14, suggesting that passenger traffic during this time period has become
more decentralized. As can be seen in Table 3 and 4, the distribution of passenger traffic is more
equally spaced out in 2011 than in 2000, whereas after the top 4 major airports (Table 3), there is
a drop of almost 20 million passengers (from Dallas to San Francisco) in 2000. In 2011, this drop
is more equal as can be seen in Table 4.
From 2001-20011, Chicago, Los Angeles, Dallas/ Fort Worth, Minneapolis, and Detroit in the U.S.2.
have experienced decreased passenger traffic.
In 2011, Houston (IAH) has emerged as a top ranking airport (#10) for passenger traffic in3.
North America. In 2000, Houston was ranked at # 17(world ranking) and wasn’t among the top
10 North American Airports for passenger traffic. In 2011, even though its ranking has gone
down to # 24 (world ranking), it still is among the top ten airports for passenger traffic in North
America (#10), indicating increased use of other airports in North America, hence reinforcing
decentralization.
Worldwide Detroit was ranked at # 16 and at # 6 for airports in North America in 2000. In 2011,4.
Detroit ranked # 42 (world rank) indicating decreased passenger traffic (see Figure 2). This
could be attributed to Detroit’s decline in manufacturing and other industries that might have
impacted passenger and cargo traffic. Detroit’s shrinking population and urban decay could also
be responsible for exacerbating the situation.
San Francisco, like Detroit has fallen down in the worldwide ranking system from # 9 to # 22 in5.
2011, which could be factored to new and emerging airports in the global scene.
Regionally, North America handles more passengers and cargo than any other worldwide region.6.
More than half of the world’s busiest 20 airports are in our region (Table 5).
Cargo movement by airports in North America showed a Gini coefficient of 0.22 in 2003 and7.
0.30 in 2013. Cargo traffic, during this time frame was more centralized than passenger traffic
which was more decentralized in North America. So, passenger and cargo movement display
reverse patterns. This could be attributed to dominance in cargo movement by the world’s largest
carriers - UPS and FedEx which operate out of Louisville and Memphis respectively. Hence cargo
movement is more centralized than passenger movement, which is decentralized.
Table 5: Top 5 passenger and cargo airports in North America
Top Passenger Top Cargo
Atlanta Memphis
Chicago O'Hare Anchorage
Los Angeles Louisville
Dallas/Ft Worth Miami
Denver Los Angeles
UPS
FedEx

7. GINI Coefficients for Passenger Traffic in North America 7
gini coefficient
Cargo movement by Ports in North America showed a Gini coefficient of 0.44 in 2001 and 0.338.
in 2011, showing that similar to passenger traffic, cargo traffic through ports became more
decentralized as well. This could also be factored to the separation of Los Angeles and Long Beach
ports into two separate ports now (in 2001 they were considered to be one port).
On a Global Scale, since 2000, airports such as those in Beijing(China), Dubai(UAE), Jakarta9.
(Indonesia), Guangzhou (China), Charlotte NC(USA), Munich (Denmark), Kuala Lumpur
(Malaysia), Istanbul (Turkey) and others have emerged in the international arena that have
increased passenger traffic. This could explain decreased and more distributed passenger traffic
in North America.
With respect to the Gini Coefficient, passenger traffic for the World, Asia and North America10.
display the same characteristics wherein the airports are more decentralized as against Europe
which is more centralized (Table 6). Europe’s centralization or passenger air travel could be
factored to its existing, well-connected, transportation networks - rail and road - which are more
favorable for short distance travel and air transport which is more favorable for long distance
travel. Furthermore, Europe’s political geography facilitates use of all forms of transportation,
and not domination of one mode over the other. This could explain decentralized use of all
transportation modes, but centralization within that mode. So, even though, passenger traffic and
freight might be distributed over land, air and water, within air transportation, airports are more
centralized.
As of now, Atlanta is the leader in passenger travel - both in North America as well the global11.
scene. However, with emerging economies in China and other South East Asian countries
(particularly in India and Indonesia), it is forecasted that Beijing, with its increasing growth
in economy as well as population, will soon surpass Atlanta in passenger travel. The number
of passengers being served by Atlanta’s Hartsfield-Jackson has continued to grow, though at a
slower rate than Beijing. Hence, there is a higher probaility of Beijing surpassing Atlanta.
Year Gini Coefficient
World
2001 0.12
2011 0.09
Europe
2003 0.19
2013 0.29
Asia
2005 0.15
2011 0.11
N. America
2000 0.17
2011 0.14
Table 6: Gini Coefficients for Passenger movement in regions around the world