Richard LycanPopulation Research Center

Portland State University, Oregon

Oregon Academy of Sciences Annual MeetingFebruary 2007

Portland Connections

Portland’s Migration Linkages from 1955-2000

Focus on Portland Metro Area

Framework for studying any metro area

Portland mainly based on current seven county metro area definition

Data for earlier periods based on older 4 county area

Some historical data presented for state

Overview of presentation

Measuring migration

Migration as a change agent

Geographic linkages in 2000

Linkages since 1955-60

Who are the movers

Sources of migration flow data

Administrative records, e.g. IRS data Register data, e.g. Sweden Census data – used in this paper

Question on long form questionnaire, 15% sample

Pre 1980 data mainly from print publications 1990, 2000, 2005 from digital files

County to county flows Public use microsample or PUMS

Not as accessible as other census data

The census question

The relevant census question asked where each person in the household lived five years ago.

The county to county flow tables provide tabulations at the county level of previous residence versus other person, housing unit, and household characteristics.

The public use microsample is more flexible, but based on smaller sample and uses counties and county groupings known as PUMAs.

Migration as a change agent The total population of an area can only change

through:

net migration (in-out migration) and natural increase (births-deaths).

For Oregon net migration generally is a more important determinant of population change than is natural increase.

Changes the composition of Oregon’s population are due in large part to the differences in the in and out migration streams

The important role of migration in Oregon’s population change

The upper graph shows the steady trend in the number of deaths and the fluctuating trend of births.

The lower graph shows the relative importance of net migration (in-out migrants) compared to natural increase (births-deaths).

-40,000

-20,000

0

20,000

40,000

60,000

80,000

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000

Net Migration

Natural Increase

0

10,000

20,000

30,000

40,000

50,000

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000

Births

Deaths

1955-60

1965-70

1985-90

1975-80

1995-2000

Periods in green covered by census question: “Where did you live five years ago?”

Gross migration as a function of region’s population and distance from Portland

Gross migration (the total movers) between two places is largely related to distance and the size of the places.

Our focus in this paper is the differences in the size of the migration streams to and from Portland, which vary due to complex economic and social forces.

PDX Migration vs. Distance - 1995-2000

WA

SEA

AK-HI

-2.00

-1.50

-1.00

-0.50

0.00

0.50

1.00

1.50 1.70 1.90 2.10 2.30 2.50 2.70 2.90 3.10 3.30 3.50

Log 10 of Distance in Miles

Log

10 o

f Per

cent

Mig

ratin

g

log (MigRate) = 3.88 -1.63 log (Distance)

R2 = .0.918 (excluding AK and HI)

Volume of spherical symbol represents number of migrants

Oregon

Washington

Rocky Mtn

California

Regions to East

Coverage of study and presentation

Migration streams to and from the Portland Metropolitan Area are presented for five year time periods from 1955-60 to 1995-2000, except for the 1975-80 time period.

Migration streams for many of the characteristics of the movers also were computed and mapped. Selected results are shown here for Hispanic status and personal income.

How to read the map

Data for 1995-2000

Net GrossIn Thousands

Think of the width of the flow-line as the diameter of a pipe

Far away regions are groups of states, nearby parts of states

The pink lines represent Portland gains, the blue represent losses

The arrowheads also show direction of net flow

Salient patterns 1995-2000 The net inflow of

29,000 persons from California the largest.

The next largest flow, collectively, is the inflow from the east.

There is a net outflow to Las Vegas and Phoenix and collectively to the Mtn. South

There is a net outflow from Portland to the remainder of Oregon

Salient patterns 1985-1990

Portland gained in-migrants from just about everywhere except Seattle.

The gains from the remainder of Oregon were large.

There were gains from Phoenix, Las Vegas and the Mtn. South.

Data not presented for 1975-80

Salient patterns 1965-1970

The patterns of gains were similar to the 1985-1990 with large gains from California and the East

There were gains from the Mtn. North but almost none from the Mtn. South.

There were small losses to Seattle.

Salient patterns 1955-1960

Portland loses population to all regions of California, the Mtn. South region, and to Seattle

There are gains from the remainder of Oregon

The Swedes and Norwegians from Minnesota and Wisconsin just keep coming.

The composition of the migrant streams

Wineberg – “Do all trails lead to Oregon”, an analysis of the 1985-90 migration data

Immutables Age, race

Changeable characteristics Income, education, poverty status

A few examples are shown, based on 1995-2000 county to county migration tables

Are movers to Phoenix and Las Vegas mainly retirees?

Phoenix

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

8.00

05-09

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

Age Group

Per

cent

Out Migration

In Migration

The largest number of movers between these two metro areas and Portland appear to be working age families and individuals

The migration from Portland to Las Vegas shows a large number of pre-retirement aged persons.

The migration from Portland to Phoenix shows a large number of retirement aged persons.

Las Vegas

0.00

1.00

2.00

3.00

4.00

5.00

6.00

7.00

05-09

10-14

15-19

20-24

25-29

30-34

35-39

40-44

45-49

50-54

55-59

60-64

65-69

70-74

75-79

80-84

85+

Age Group

Per

cent

Out Migration

In Migration

Where do Hispanics come from? 8,420 come from

California, especially from Los Angeles. An additional 21,600 come from abroad, mainly from Mexico

A modest number come from Washington and Oregon outside PDX.

There is net out-migration from Portland to the Southeast Region

Income of movers to and from PDX

To PDX - From PDX

-10,000 -5,000 0 5,000 10,000

Average Income

0 5,000 10,000 15,000 20,000 25,000 30,000 35,000 40,000 45,000

Spokane

Northeast

Southeast

East North Central

West North Central

Fresno

Mountain South*

Boise

San Diego

Mountain North*

West South Central

Washington*

Seattle

Alaska - Hawaii

Salt Lake City

Phoenix

Los Angeles

California*

Sacramento

Reno

Las Vegas

San Bern'o - Riverside

San Francisco

San Jose

From PDX

To PDX

Movers from PDX to San Jose to have considerably higher incomes than for San Jose to PDX movers.

The opposite is true for Spokane where Portland gains in higher income movers.

The San Jose – PDX movers have very high incomes in both directions, half again as high as those between PDX and Spokane.

Conclusions

Have tools available to easily extract migration stream data from the 1990 and 2000 census

Plan to expand paper into a monograph

Understanding the meaning and significance of the data is more difficult than extracting the data.

I welcome suggestions on variables of interest.

County to County Migration Tables

for the 1990 Census

1. RACE(5) BY HISPANIC ORIGIN(2) BY SEX(2) BY AGE(18) 2. RACE(5) BY SEX(2) BY PLACE OF BIRTH AND CITIZENSHIP(68) 3. HISPANIC ORIGIN(3) BY SEX(2) BY PLACE OF BIRTH AND CITIZENSHIP(68) 4. RACE(5) BY SEX(2) BY AGE(12) BY HOUSEHOLD TYPE(4) BY TENURE(2) 5. HISPANIC ORIGIN(3) BY SEX(2) BY AGE(12) BY HOUSEHOLD TYPE(4) BY TENURE(2) 6. RACE(5) BY AGE(12) BY HOUSEHOLD TYPE(4) BY POVERTY STATUS(3) 7. HISPANIC ORIGIN(3) BY AGE(12) BY HOUSEHOLD TYPE(4) BY POVERTY STATUS(3) 8. RACE(5) BY SEX(2) BY AGE(9) BY INCOME IN 1989(11) 9. HISPANIC ORIGIN(3) BY SEX(2) BY AGE(9) BY INCOME IN 1989(11) 10. RACE(5) BY SEX(2) BY AGE(12) BY POVERTY STATUS(3) BY TENURE(2) 11. HISPANIC ORIGIN(3) BY SEX(2) BY AGE(12) BY POVERTY STATUS(3) BY TENURE(2) 12. RACE(5) BY SEX(2) BY AGE(9) BY EDUCATIONAL ATTAINMENT(7) 13. HISPANIC ORIGIN(3) BY SEX(2) BY AGE(9) BY EDUCATIONAL ATTAINMENT(7) 14. RACE(5) BY SEX(2) BY AGE(8) BY EMPLOYMENT STATUS(4) BY COLLEGE ENROLLMENT(2) 15. HISPANIC ORIGIN(3) BY SEX(2) BY AGE(8) BY EMPLOYMENT STATUS(4) BY COLLEGE ENROLLMENT(2) 16. RACE(5) BY SEX(2) BY AGE(8) BY EMPLOYMENT STATUS(4) BY POVERTY STATUS(3) 17. HISPANIC ORIGIN(3) BY SEX(2) BY AGE(8) BY EMPLOYMENT STATUS(4) BY POVERTY STATUS(3) 18. SEX(2) BY AGE(8) BY OCCUPATION(13) BY POVERTY STATUS(3) 19. SEX(2) BY AGE(8) BY INDUSTRY(17) BY POVERTY STATUS(3) 20. RACE(5) BY SEX(2) BY AGE(12) BY TENURE(6) 21. HISPANIC ORIGIN(3) BY SEX(2) BY AGE(12) BY TENURE(6)

Selected References Cortright, Joseph, Impresa Inc., ”The Economic Importance of Being Different:

Regional Variations in Tastes, Increasing Returns and the Dynamics of development, Economic Development Quarterly, Vol. 16 No. 1, February 2003, pp. 3-16.

Cortright, Joseph, Impressa Inc., The Young and the Restless, How Portland Competes for Talent, undertaken by Impressa Inc. for the Portland Development Commission, Westside Economic Alliance, City of Beaverton, City of Hillsboro, City of Tualatin, and Nike, 2007. See the CEO’s for Cities website <www.ceosforcities.org/conversations/smartcity/index.php>.

Southeast Michigan Council of Governments, Migration and its Impact on Southeast Michigan, 1990-2003, Detroit, Michigan, November 2004, <www.semcog.org>.

Howard Wineberg, Do All Trails Lead to Oregon? An Analysis of the Characteristics of People Moving to and from Oregon, 1985-1990, Population Research Center, Portland State University, 1995.

Contact information

Richard LycanPopulation Research CenterPortland State UniversityPortland, Oregon 97207-0751lycand@pdx.edu

Copy of paper and additional maps available on CD