Urban Hierarchy and the "Rank-Size Rule"

by Prof Kilkenny for Econ 376 “Rural, Urban, and Regional Economics”

 

The approximate RANK-SIZE RULE equation is:   Rank r = C / popr 

 

In words: The rank of city “r” in a region

(“rank” = how many cities are at least as large or larger than it)

is equal to the ratio of the population of the region’s largest city (“C”)

divided by the population of city r (“popr”).

 

Equivalently: C = rankr•popr

and Popr = C/rankr

 

Graphically: plot city populations sorted in descending order.  The locus is a linear hyperbola (C=R•P) .

 

SEE TABLE BELOW

Sources: 2000 city population data from  Ranking Tables for Incorporated Places of 100,000 or More: Population in 2000 and Population Change from 1990 to 2000 (PHC-T-5)” http://www.census.gov/population/www/cen2000/phc-t5.html .  1990 data from Statistical Abstract of the United States, 1991 (Washington, D.C.: Government Printing Office). Prior years from Table 4, in Mills and Hamilton, Urban Economics 5th Edition, page 74, data: U.S. Department of Commerce, Bureau of the Census. Census of Population, 1972, 1982.

 

Note that (i) The largest cities are port cities.

          (ii) They are as far apart geographically (dispersed) from each other as possible.

          (iii) The relative sizes of cities in rank persist over time

(e.g., NY (#1 in 1870) was twice the size of Philadelphia (#2 in 1870), etc). In other words, the largest city has had twice the population of the second largest, and three times the third, and so on; no matter which cities were 2nd or 3rd, and no matter when.

 

Fun things to do with the “rank-size-rule.” Amaze your friends and family:  All you need to remember is the population of New York City (about 8 million).

 

1. You’re driving cross-country and pass the sign “Entering Houston, Population 2 million.”  You can immediately inform everyone in the car that Houston is the fourth largest city in the USA. 

 

2. Your friend says “L.A. is the second largest city in the USA. “  You say, “Right, and it’s population is about 4 million.”

Population of Selected Cities, Selected Years, 1790 to 2000

City (not MSA)

RANK

Population (in Thousands: 1,000s)

% change

 

2000

1990

1910

1790

1850

1910

1970

1990

2000

90-00

New York

1

1

1

49

696

4,767

7,896

7,323

8,008

9.4%

Los Angeles

2

2

15

 

       2

319

2,812

3,485

3,695

6.0%

Chicago

3

3

2

 

     30

2,185

3,369

2,784

2,896

4.0%

Houston

4

4

 

 

       2

79

1,234

1,631

1,954

19.8%

Philadelphia

5

5

3

29

121

1,549

1,949

1,586

1,518

-4.3%

Phoenix

6

9

 

 

 

 

   584

983

1,321

34.3%

San Diego

7

6

 

 

 

 

   697

1,111

1,223

10.2%

Dallas

8

8

 

 

  

92

844

1,007

1,189

18.0%

San Antonio

9

10

 

 

 

 

 

935

1,145

22.3%

Detroit

10

7

10

 

21

466

1,514

1,028

  951

-7.5%