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Christopher Bradford
April 7, 2013
Prof. Becker, Urban Econ
Durham Paper
The Research Triangle Park as a Regional Employer and Engine of Growth
(NOT planning on expanding for term paper)
Introduction
Since its establishment in 1959, the Research Triangle Park (RTP) has been a prominent
fixture in the regional economy. North Carolina’s historical textile, tobacco and furniture industries
experienced significant decline in the decades following the Second World War, and many jobs were
lost in what is now the Research Triangle area (Link and Scott 2003). In the 1950s, several figures in
state and local government, business and academia began to discuss development plans to increase
employment and diversify the regional economy (Link 1995). The culmination of these efforts was
the RTP, a complex that would focus on burgeoning high-technology industries. The RTP “began”
in earnest in 1959, when the Research Triangle Institute and the Chemstrand Corporation located in
the park (Link and Scott 2003).
Since then, the RTP has grown significantly. The RTP’s success can be measured by the total
number of firms that occupy the park and by the total employment of these firms. Both of these
metrics have generally increased throughout the past five decades. Today, the RTP houses 178 firms
that cumulatively employ over 39,000 workers. Analysis of the composition of RTP firms reveals a
trend whereby most recent entrants to the park are smaller firms with relatively few employees. The
RTP’s success as a regional employer and engine of economic growth is also suggested by secondary
metrics such as the growing average income in the area since the park’s creation.
The RTP’s substantial growth over its five-decade existence can be examined by considering
the park as an agglomeration economy. The park has grown by attracting firms that specialize in
high-technology fields. As the number of firms specializing in similar fields has grown, so have the
agglomeration advantages of the RTP. Yet despite the RTP’s past successes as a regional employer
and engine of economic growth, questions exist about the sustainability of its suburban industrial
cluster model moving forward.
Literature Survey
The RTP can be viewed as an agglomeration economy that specializes in high-technology
industries, particularly in the life sciences and information technology (see Figure 6). Alfred Marshall
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(1890) claimed that economic clustering provides benefits in terms of labor pooling, information
flow and access to specialized inputs. Saxenian (1994) proposes that agglomeration economies are
particularly important for high-technology industries. Through physical proximity, scientists,
engineers and managers can develop localized networks for efficient information sharing and
innovation. Jenkins et al (2008) argue that the agglomeration effects of research parks are significant
and are responsible for increasing the proportional growth of jobs in high-technology industries.
One of the RTP’s prominent agglomerative features is the high level of educational
attainment of the park’s employees and of the residents of the Triangle region more broadly. Fortysix percent of the workforce in the 13-county Triangle area held college degrees in 2011, well above
the national and state averages of 36% and 26.5%, respectively (US Census Bureau 2013). Moretti
(2003) finds that for each one-percentage increase in the share of college degree holders in a MSA,
the average wage for all workers rises by between 0.6 and 1.2%.
Glaeser and Saiz (2003) find evidence that highly skilled cities, where a high percentage of
workers have college or advanced degrees, are becoming more productive and growing faster than
less-skilled cities. The authors cite the importance of human capital in allowing cities to “reinvent”
themselves and adapt to economic change. The Triangle region illustrates aspects of such a
“reinvention city,” having transformed itself in a half-century from an economy predicated on
cigarette, textile and furniture manufacturing to a highly educated technological hub. Goldstein
(2005) argues that it has been the development of the Triangle region’s knowledge infrastructure that
has transformed the area in recent decades. He reasons that the success of the RTP owes much to
the three prominent research universities in the area – Duke University, UNC-Chapel Hill and NC
State University. RTP firms and these universities have mutually benefitted from one another’s
presence, with firms gaining research experience and universities learning how to better
commercialize their own research.
Kodrzycki and Muñoz (2009) find that leadership and long-term collaboration between the
public and private sectors are essential for the economic revitalization of post-industrial areas such
as the Triangle region. Several studies (Link 1995 and 2003, Rohe 2011) emphasize the creative
leadership and close cooperation between private industry, the Triangle’s three leading universities
and local and state government that has allowed the RTP to thrive. Sternberg et al (2010) describe
the RTP as a cluster driven by the private sector but dependent upon cooperation with state
government and several regional nonprofit organizations, such as the Research Triangle Foundation
(RTF) and Research Triangle Regional Partnership (RTRP). Goldstein (2005) emphasizes the
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importance of public sector investments for attracting firms to the RTP, citing in particular the
expansion of the Raleigh-Durham International Airport and Interstate 40.
However, there is much literature that questions the efficacy of industrial clustering in
today’s rapidly changing economic climate. Ioannides et al (2008) predict that increasingly cheap and
efficient information sharing, particularly due to the Internet, will lead to more spatially diffuse
economic activity. The authors also predict that larger cities will experience more rapid economic
and population growth than smaller cities, as larger cities typically have more robust consumer
amenities and are thus more attractive to young professionals. These predictions imply that isolated
suburban clusters such as the RTP may be outmoded economic engines in the future.
Moreover, in a comparison of numerous counties similar in terms of population and hightechnology employment, Wallsten (2004) finds that research parks typically exert no positive effect
on regional economic development. Analyzing high-technology clusters in Texas, De Silva and
McComb (2011) find that positive locational effects exist for firms in the same industry located
between one and 25 miles apart. Locating within one mile of a same-industry firm, on the other
hand, correlates with increased firm mortality.
In contrast to these skeptical prognoses on the merits of high-technology clustering, Weddle
et al (2006) contend that the RTP has exerted substantial economic spillover effects beyond the
park’s boundaries. The percentage of firms engaged in “new-line” industries, including chemicals,
electronics, communications, business services and engineering, rose from 15% at the time of the
RTP’s founding to 51% in 2001. The authors attribute growth in these sectors to the presence of
RTP firms engaged in new-line industries. In sum, vastly different opinions exist in the literature on
the efficacy of industrial clustering.
Description of Data
The economic growth of the RTP can be viewed in terms of the number of firms that have
located in the park over time. As shown in Figure 1, the number of RTP tenants has steadily
increased by the decade. As of January 2013, 178 firms are located in the RTP, up from 21 at the
end of the 1960s. The number of firms nearly doubled, from 21 to 38, in the 1970s. The park
experienced its most significant numerical increase in tenants between 2000 and 2007, adding 45
firms in this period.
Figure 2 shows patterns of RTP firm entry over time according to current number of
employees. Data were available for 168 of the 178 firms currently located in the RTP. Of these 168
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firms, 120, or over 70%, have fewer than 50 employees. The vast majority of firms that employ
fewer than 50 entered the RTP recently: over 88% of these firms have entered since 2000, with 35%
having entered since 2010. Firms with small workforces display the most temporally skewed entry
pattern. Of the 16 firms employing between 50 and 99 workers, half entered the RTP before 1990.
Of the ten firms employing between 100 and 249, four entered before 1990. Seven of the 12 firms
with 250-999 employees entered before 1990. Half of the ten largest firms with over 1000 employees
entered before 1990. While they represent a far smaller sample size, larger employers have entered
the park with a far more even temporal distribution than firms with employment below 50.
Historically, as the number of firms housed in the park has grown, so has the park’s total
employment. Today, the RTP’s cumulative full-time employment stands at around 39,000 (RTF). As
shown in Figure 4, total RTP employment increased annually with only one exception in the years
from 1960 to 2000. Total employment has grown with something of a bi-sigmoidal distribution, with
rapid increases in the mid-1960s and again in the early to mid-1980s. The significant employment
increase from 1965 to 1966 is due to the entry of IBM and what is now the National Institute of
Environmental Health Sciences (NIEHS), both of which were and remain very large employers
(Link and Scott 1995). The 1980s oversaw a tripling in employment in the park, from just over
10,000 at the beginning of the decade to well over 30,000 by the end. However, beginning in the
early 2000s, total employment declined from a peak of over 43,000 employees to around 37,000. In
this period, the RTP and the surrounding region experienced an acute decline in the
telecommunications industry. Nortel Networks in particular was responsible for a large number of
lost jobs in the RTP. The firm had over 8,500 RTP employees in the late 1990s, but cut RTP
employment to 1,850 by 2009, when Ericsson acquired the struggling company (Rohe 2011).
In the formative years of the RTP, developers pursued a recruitment strategy aimed at large
corporations (Rohe 2011). The entry of IBM, NIEHS, Glaxo (later GlaxoSmithKline) and the EPA
were major boons for the RTP in its early years. Large firms still feature prominently in the RTP.
Currently, IBM and GlaxoSmithKline employ some 10,000 and 4,500 workers respectively (Greater
Durham Chamber of Commerce). However, a large and increasing number of current RTP tenants are
smaller employers. As shown in Figure 5, 43% of RTP firms in 2013 have fewer than 10 employees.
Sixty-two percent of firms employ fewer than 25, and 71% employ fewer than 50 workers. Figure 6
illustrates the industries in which current RTP firms specialize. Biotechnology/life sciences dominate,
with 45% of firms involved in these fields. A further 18% of RTP firms are engaged in information
and communication technology. The RTP has attracted firms in these industries throughout its
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existence. Of the 24 current tenants that entered the park by 1979, 10 specialized in biotechnology/
life sciences or information and communication technology.
Data on the Triangle region indicate a correlation between the park’s growth and regional
economic success. Since the establishment of the RTP, income in the area has grown considerably
compared to state and national averages. In 1969, when the RTP housed 21 firms, average per capita
income was 86% and 89% of the national average in the Durham-Chapel Hill and Raleigh-Cary
MSAs, respectively (Figure 8). Relative per capita income peaked for the Durham-Chapel Hill MSA
in 1993, at 105% of the national average, and for the Raleigh-Cary MSA in 2000, at 115%. In 2007,
these figures were 104% and 102%, respectively. Though a crude metric that fails to discern between
employees of different firms, the average salary for an employee of an RTP company was $56,000 in
2004. This figure is 45% above the national average and roughly 30% higher than the average
income for both the Durham-Chapel Hill and Raleigh-Cary MSAs (Weddle et al 2006).
Analysis
The increase in the number of firms occupying the RTP over time is a testament to the
agglomeration effects from which the park benefits. As the number of tenant firms specializing in a
certain field has grown, the RTP’s agglomeration effects have in turn increased. Agglomeration
effects are especially pronounced for RTP firms specializing in biotechnology/life sciences, with
around 80 firms operating in this sector today. The RTP benefits significantly from the abundance
of well-educated professionals in the regional labor pool. Highly educated workers are essential to
the RTP: in 2006, five percent of the RTP’s employees held a PhD (Weddle 2006). In 1998, onequarter of new professional employees hired by RTP firms held degrees from UNC-Chapel Hill,
Duke or NC State University (Link 2002). According to Rohe (2011), these universities have
cooperated increasingly with RTP firms to commercialize research since the 1980 Bayh-Dole Act.
Data show a pattern whereby smaller firms that employ relatively few workers have tended
to enter the park more recently. Additionally, there appears to have been a great deal of firm
turnover in the RTP in recent years. While direct data on firm exits from the RTP was not available,
secondary analysis of firm entry indicates significant turnover. Though entry data for 10 firms are
missing, of the 21 firms housed in the RTP by 1969, only 7 are currently listed as tenants. Of the 38
tenants housed by 1979, 22 remain. Thirty-six of the 70 firms housed in the park in 1989 remain.
Sixty of the 112 firms housed in 1999 remain, as do 122 of the 157 firms located in the park by 2009.
Currently, the RTP houses 178 firms, up from 157 in 2007. However, 63 firms entered the park
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between 2008 and 2013. Again, the implication is that numerous firms must have left the RTP over
this period. It is likely that many of these exiting firms were start-ups nurtured in the RTP that then
left the park. Indeed, according to the RTF, the five incubators and business accelerators in the RTP
have helped establish over 250 start-up and spin-off firms over the years. Goldstein (2005) notes
that the RTP has had considerable success in creating spin-off firms in the past two decades, but has
failed to catalyze the growth of larger high-technology facilities beyond the park’s boundaries.
It appears that the trend whereby smaller firms comprise a higher percentage of the RTP’s
total tenants reflects a desire on behalf of planners to attract start-ups. On its website, the RTF
prominently advertises the park’s five incubators and business accelerators, which currently nurture
“nearly 80 start-up and early state companies.” The RTF states that flexible, cost-efficient leases are
available for start-ups, and specifically for start-ups that have emerged from university research. This
strategic emphasis on attracting smaller firms may be partly due to the fact that only 700 acres are
free for development in the park (RTF). Nonetheless, in the RTF’s 2012 “Master Plan” for future
development of the park, leaders called for a continued effort to maintain existing large firms in the
RTP as well as to attract new large firms. The plan proposes that the park further diversify its
tenants by industry and size to ensure the RTP’s continued success.
The campaign to attract start-ups also likely recognizes increased competition for attracting
large firms, as well as changes in overall corporate strategies for research and development. Depillis
(2012) argues that many large companies are reluctant to make the costly long-term investments in
permanent infrastructure that they did in the RTP’s infancy. Instead, firms increasingly prefer to
lease space for projects on an ad hoc basis. Depillis also suggests that the RTP’s isolated, sprawling
complexes are unappealing to many young professionals. To address changes in employee
preferences, the RTF has called for a renovation of the park that will implement residential and
commercial spaces (Rohe 2011). However, in addition to requiring substantial changes in zoning
laws, this plan has met with doubts that employees, especially young professionals, want to live and
work in a suburban business campus.
The growth of the RTP in terms of the park’s number of tenants and employees over the
years has indeed coincided with economic growth in the Triangle region (Figures 7 and 8). Average
wages have risen, unemployment has remained below national and state averages and population has
increased (Rohe 2011). Weddle et al (2006) argue that the growth of the RTP has exerted spillover
effects that have spurred the growth of new-line industries in the counties surrounding the park.
Total employment in the seven counties closest to the park increased by nearly 700,000 between
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1970 and 2006. These gains were most pronounced in the core counties of Wake, Orange, and
Durham, all of which experienced employment increases of well over 200% in this period (Rohe
2011). Hence, regional employment growth in the past several decades has correlated with greater
proximity to the RTP. Weddle et al (2006) also note that the RTP contributes to the regional
economy directly in terms of construction employment and real estate, income and sales tax yields.
However, while it is notable that the successes of the RTP have correlated with regional economic
growth, it is difficult to establish a causal relationship between the former and the latter.
Though the RTP has certainly exerted positive economic effects on the surrounding area, it
is unreasonable to conclude that the park is single-handedly responsible for regional economic
growth. In the 13-county Triangle area, population increased by 29.2% from 2001-2011, compared
to the national average of 9.3% (NCOSMB, US Census Bureau). However, during this period, the RTP
shed several thousand jobs. Total park employment began to rebound in 2005 and has continued to
grow since, but today’s employment figures are still below the peak of the early 2000s. The rapid
population growth in the area despite the park’s decreasing employment in the past decade suggests
that other features of the regional economy must have appealed to immigrants. Healthcare and
education are two candidates: the two sectors have been the region’s fastest-growing industries over
the past two decades (NC Dept. of Commerce).
Additionally, the growth of the RTP has certainly not proven to be a panacea for issues of
poverty and income inequality that plague parts of the Triangle. In 2009, nearly 19% of Durham city
residents lived in poverty, with poverty rates at 25.7% for black and 36.3% for Hispanic residents. In
addition, the median household income for white families, over $61,000, was far higher than the
figures for black ($33,000) and Hispanic ($38,000) families (City Data). These economic malaises of
the Triangle area require solutions that the RTP has proven unable to provide.
Conclusions
Data have illustrated that in terms of the total number of firms and total employment, the
RTP has grown substantially over the past five decades. The park’s 178 firms currently employ
around 39,000 full-time workers. The RTP has illustrated a trend in recent decades toward housing
an increasing number of smaller, lower-employing firms. As of January 2013, 71% of the RTP’s 178
firms employ fewer than 50 workers, with 43% of its firms employing fewer than 10 (Figure 5). The
park appears to be successful in attracting new firms, having added 106 new firms since 2000 and 46
since 2010 (Figures 2,3). Substantial regional economic growth has occurred since the park’s
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founding, as evidenced by the growth of regional income compared to the national average (Figures
7,8).
Yet the RTP faces numerous challenges in retaining its competitive advantage in hightechnology employment in the years to come. With less than one-tenth of its total area available for
development, the RTP faces spatial constraints that limit its ability to attract the large firms that
drove the park’s early growth. Competition for attracting new firms has increased greatly with the
proliferation of research parks and development initiatives both domestically and internationally.
Moreover, the RTP faces a decline in several of its prominent industries. From 1999 to 2003, the
park experienced a 30% decline in employment in the manufacturing of high-technology equipment
(Rohe 2011). Additionally, the information technology sector, long a large employer in the RTP, has
suffered over the past two decades. The park has lost thousands of jobs in this sector since the late
1990s, as evidenced by the decline of Nortel Networks.
The data indicate that the RTP has been fairly successful in attracting new firms with small
staffs. However, the turnover rate has been high for these firms. One possible implication of this is
that once start-ups mature sufficiently, they find the environment of the RTP undesirable or
unfavorable to their sustained growth. The isolated nature of the RTP complex itself might
contribute to this pattern. A 1988 survey of RTP firms found that 47% of these companies would
not have located in the Triangle area if the RTP had not existed (Rohe 2011). It would be instructive
to conduct a contemporary equivalent of this survey to observe whether the features of the park still
proved as attractive to firms, or whether firms desired new amenities not offered by the RTP.
Moving forward, it remains to be seen whether the efforts to modernize the RTP as a
mixed-use complex featuring residential and commercial space are successful in attracting new firms
and workers to the park. More fundamentally, further research is needed to determine the role of
traditional suburban research parks in housing start-ups and small firms specializing in hightechnology fields. The RTP contributed hugely to modernizing the regional economy in the latter
half of the 20th century following the decline of traditional manufacturing in the area. Today, the
park’s leaders must demonstrate a similar ability to adapt to new trends in employment in order to
preserve the RTP’s status as a successful regional employer and engine of economic growth.
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Appendix
Figure 1
Number of Firms in RTP
Number of Firms
200
150
100
50
0
1969
1979
1989
1999
2007
2013
Year
Data from: Rohe 2011.
Figure 2
Entry of Current RTP Firms by Number of Employees
50
Number of Firms
40
Under 50 Employees
30
50-99 Employees
100-249 Employees
20
250-999 Employees
1000+ Employees
10
0
1959-1969
1970-1979
1980-1989
1990-1999
Years
2000-2009
2010-2013
Data from: “2013 Company Directory.” Research Triangle Foundation of North Carolina. 2013.
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Figure 3: Data on Firm Entry
Date of Entry for All Current Firms (data
available for 168 of 178 current tenants)
Year
Number of Firms
% all Firms
1959-1969
7
1970-1979
15
1980-1989
14
1990-1999
24
2000-2009
62
2010-2013
46
168 total
100% total
Under 50
Employees
1959-1969
1970-1979
1980-1989
1990-1999
2000-2009
2010-2013
Number Firms
3
5
4
14
52
42
% Firms this size
2.5
4.2
3.3
11.7
43.3
35
100% total
1
4
3
1
4
3
% Firms this size
6.25
25
18.75
6.25
25
18.75
100% total
120 total
50-99 Employees
1959-1969
1970-1979
1980-1989
1990-1999
2000-2009
2010-2013
Number Firms
16 total
4.2
8.9
8.3
14.3
36.9
27.4
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100-249
Employees
1959-1969
1970-1979
1980-1989
1990-1999
2000-2009
2010-2013
250-999
Employees
1959-1969
1970-1979
1980-1989
1990-1999
2000-2009
2010-2013
1000+ Employees
1959-1969
1970-1979
1980-1989
1990-1999
2000-2009
2010-2013
Number Firms
% Firms this size
0
2
2
4
2
0
0
20
20
40
20
0
10 total
100% total
Number Firms
% Firms this size
0
2
5
3
1
1
0
16.7
41.7
25
8.3
8.3
12 total
100% total
Number Firms
% Firms this size
30
20
0
20
30
0
100% total
3
2
0
2
3
0
10 total
Data from: “2013 Company Directory.” Research Triangle Foundation of North Carolina. 2013.
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Figure 4: Total Employment of RTP Firms
Source: The Research Triangle Foundation of North Carolina.
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Figure 5
RTP Firm Size: Number of Employees 2013
(178 total firms)
0.03 0.02
1 to 9
0.07
10 to 24
25 to 49
0.43
0.17
50 to 249
250 to 999
0.09
1,000 to 4,999
5,000+
0.19
Data from: Research Triangle Foundation of North Carolina. 2013.
Figure 6
Industries of RTP Firms 2013
(178 total firms)
0.02 0.02
0.07
Life Sciences
0.08
Info Technology
0.45
0.09
Professional Business Services
Scientific Associations
Materials Science & Engineering
Service Providers
0.09
Environmental Sciences
Financial Activities
0.18
Data from: Research Triangle Foundation of North Carolina. 2013.
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Figure 7
Average Per Capita Personal Income,
Durham-Chapel Hill and Raleigh-Cary MSAs
45000
40000
Avg Income $
35000
30000
25000
20000
Durham-Chapel Hill MSA
15000
Raleigh-Cary MSA
10000
5000
0
1969
1975
1981
1987
1993
Year
1999
2005
2011
Data from: Economagic.com. 2013.
Figure 8
Average Per Capita Personal Income
Compared to US Average (100)
140
Income Ratio
120
100
80
Durham-Chapel Hill MSA
60
Raleigh-Cary MSA
40
20
0
1969
1975
1981
1987
Data from: Economagic.com. 2013.
1993
Year
1999
2005
2011
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