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D Y N A M I C  E C O N O M E T R I C  M O D E L S  
DOI: http://dx.doi.org/10.12775/DEM.2018.007  Vol. 18 (2018) 115−127 

Submitted October 29, 2018  ISSN (online) 2450-7067 
Accepted December 28, 2018 ISSN (print) 1234-3862 

Ewa Majerowska, Magdalena Gostkowska-Drzewicka* 

Impact of the Sector and of Internal Factors  
on Profitability of the Companies Listed  

on the Warsaw Stock Exchange 

A b s t r a c t. The aim of the article is to assess the impact of the sector environment and of 
selected internal factors on the profitability level of the companies listed on the Warsaw Stock 
Exchange in 1998–2016. An increase in the financial leverage, financial liquidity, non-debt tax 
shield and enterprise size cause a drop in the ROA. An increase in the ratio of fixed assets to 
the total assets results in an increase in the ROA. Similar results were obtained for the models 
estimated for the ROE. It means, that profitability of the examined companies results from the 
decisions made by the managers and from the impact of the sector environment. 

K e y w o r d s: return on assets (ROA), return on equity (ROE), industry effect, panel estima-
tion. 

J E L Classification: G30. 

Introduction  
Identification of the factors shaping enterprise profitability is an important 

research trend that has been considered on many levels of economic sciences. 
In the traditional approach that is based on the S-C-P concept (Structure-Con-
duct-Performance), industrial economics focuses on the sectoral factors shap-
ing the competitive advantage. These determinants entail the concentration, 
the scale effect as well as the entry and exit barriers (Porter 1992; Slater and 

                                                
* Correspondence to: Ewa Majerowska, Faculty of Management, University of Gdańsk, 

ul. Armii Krajowej 101, 81-824 Sopot, Poland, e-mail: ewa.majerowska@ug.edu.pl; Magda-
lena Gostkowska-Drzewicka, Faculty of Management, University of Gdańsk, ul. Armii Kra-
jowej 101, 81-824 Sopot, Poland, e-mail: mgostkowska@wzr.ug.edu.pl. 



Ewa Majerowska, Magdalena Gostkowska-Drzewicka 

DYNAMIC ECONOMETRIC MODELS 18 (2018) 115–127 

116 

Olson, 2002). By contrast, in accordance with the RBV concept (Resource-
Based View), the role of company-specific internal factors is emphasized. Ac-
cording to this approach, the organizational structure and the managers’ man-
agerial skills are the source of the differences in the level of profitability of 
individual companies. Discussion has been continuing in the literature on the 
subject about the impact of both groups of factors on the financial results of 
enterprises. The attempts to confirm the validity of both approaches have been 
supported by many empirical studies, the results of which, however, are am-
biguous. The hypothesis formulated assumes, therefore, that both the sector 
environment and the internal factors exert specific impact on the level of 
a given entity’s profitability. Moreover, profitability is the main pillar for any 
company to survive in the long run. For this reasons, the aim of the article is 
to assess the impact of the sector environment and of selected internal factors 
on the profitability level of the companies listed on the Warsaw Stock Ex-
change in the years 1998–2016. 

Implementation of a goal formulated as such and verification of the re-
search hypothesis required estimation of panel data models. To group the ex-
amined enterprises according to their sectoral affiliation and to estimate the 
impact of the sector on their financial results, the sectoral classification used 
for the needs of the Warsaw Stock Exchange was applied. The profitability 
(ROA) and the capital (ROE) ratios of the examined entities were adopted as 
the dependent variables. The sector environment (INDUSTRY) is one of the 
independent variables. Other exogenous variables are the internal factors. The 
value of debt (LEVERAGE) has been expressed as the total debt and total 
assets ratio, thus it describes the structure of the capital, which is identified 
with the structure of financing. The growth rate (GROWTH) has been de-
scribed by the percentage change in the sales revenue, relative to the previous 
year. Financial liquidity (LIQ) has been designated as the ratio of current as-
sets to current liabilities. The non-debt tax shield (NDTS) was calculated as 
the ratio of the depreciation to the total assets. The natural logarithm of the 
total assets’ value has been assumed as the volume (size). The structure of 
assets (TANG), also referred to as asset flexibility (tangibility), has been de-
scribed by the ratio of the tangible fixed assets to the total assets. Calculations 
were carried out using the GRETL package. 

The article consists of an introduction, four parts and an ending. The first 
part concerns the shaping of the enterprise performance results, in the context 
of the positional and the resource-related concept of the competitive ad-
vantage. In the second part, an overview of the studies based on these theories 
was made. The third part is methodical. The following part presents the results 
of the research, which have been summarized in the final part of the paper.  



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1. Enterprise Profitability in the Light of the Positional and  
the Resource-related Concept of the Competitive Advantage  
The factors shaping enterprise profitability can be classified as: internal 

factors (specific for a given entity), those related to the sector environment 
and to the macro-environment (Pierścionek, 1997, p. 105–107). Impact of the 
internal factors and of the sector environment on the company's financial re-
sults can be considered in the light of two opposing concepts of the competi-
tive advantage: the positional and the resource-related school of thought.  

Supporters of the positional school of thought emphasize the role of the 
sector environment in shaping the results of enterprise performance. The clas-
sic research approach consistent with this theory is the aforementioned S-C-P 
concept (Structure-Conduct-Performance), initiated by Bain (1951). It should 
be emphasized that the sector structure determines the activities of enterprises, 
in terms of price formation, research and development or investments, which 
in turn affect their financial results. Due to the superior role of the sector, im-
pact of managerial decisions on the company's profitability is thus limited. 
In his pioneering work, Bain (1951) proved that the average level of profita-
bility obtained by the enterprises belonging to the sectors with a high degree 
of concentration is higher than in dispersed industries. The greater degree of 
concentration provides these companies with a bargaining advantage and the 
ability to put pressure on the partners. 

In contrast to the positional school of thought, the RBV (Resource-Based 
View) approach exposes the importance of internal factors in achieving a com-
petitive advantage. This means that the key role in shaping a company's finan-
cial results is the way of managing the assets it owns (Wernerfelt, 1984; Bar-
ney, 1991). Therefore, market success of a company is determined by the abil-
ity to use the available resources, owing to which it is able to develop a highly 
competitive position.  

Porter (1992, p. 21–23; 2008), emphasizes that relating a company to its 
environment constitutes the essence of a competition strategy formulation. 
The concept of five competitive forces developed by this researcher refers to 
the structural features of a sector, which determine the strength of the compet-
itive forces, and therefore the level of profitability. This means that different 
sectors vary, in terms of the ultimate potential for generating profit. This au-
thor subjected this thesis to verification in his later works (Porter, 1991; 
McGahan and Porter, 1997). The research carried out confirmed, to a certain 
extent, previous observations. It turned out that both the sector-related and the 
internal factors had impact on the profitability of the examined enterprises. 
Porter (1991) emphasizes that a company is partly under the influence of the 
sector environment, however, to some extent, it can also affect it. Therefore, 
it is possible to determine to what extent a company's financial results are 



Ewa Majerowska, Magdalena Gostkowska-Drzewicka 

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118 

shaped by the sector environment and to which by the internal factors associ-
ated with the decisions made by management.  

2. Overview of the Studies on the Factors Shaping the Results  
of Enterprise Performance 
Impact of the sector environment and internal factors on the profitability 

of enterprises has been the subject of numerous studies. Their results are di-
versified, ambiguous and even contradictory. Schmalensee (1985) analyzed 
the impact of the sector on the financial results of enterprises, on a sample of 
456 US manufacturing companies, for the year 1975. The author stated that 
the sectoral effect is the key factor shaping the profitability of the examined 
entities and explains about 19% of their financial results. The same research 
shows that the internal factors, affecting profitability from the level of an en-
terprise, have negligible impact on it. Rumelt (1991) conducted analogous an-
alyzes for the period of 1974–1977, in which he included 432 to 471 produc-
tion enterprises for each year. This author obtained opposite results. Accord-
ing to him, the sectoral effect was not significant, it explained only 4% of the 
volatility of the profitability ratios in the examined entities. On the other hand, 
internal factors were shown to have significant impact on the profitability of 
the examined entities (44%). However, in the studies carried out by both cited 
authors, a very short period of time was analyzed, which could significantly 
distort the results obtained by them. In response to the studies carried out by 
Rumelt (1991) and Schmalensee (1985), McGahan and Porter (1997) ana-
lyzed a much longer period, covering all phases of the business cycle, i.e. 
1981–1994 on a sample of 5196 US companies from all sectors, except the 
finance sector. The research conducted showed that the sectoral effect ex-
plained 19% of the volatility of the profitability ratios in the examined entities. 
What is more, the strength of this effect varied, depending on the sector. And 
so, the sectoral effect was of less significance in the case of manufacturing 
enterprises, and of larger importance in entertainment, commercial and trans-
portation industries. In turn, internal factors explained the financial results of 
the surveyed entities in as many as 32%. 

The studies conducted by Bamiatzi and Hall (2009), on a sample of as 
many as 71750 entities operating in Great Britain in the years 2002–2004, 
show that the financial results of micro-, small- and medium- as well as large-
sized enterprises during the analyzed period were affected by both the sectoral 
factors, and the internal ones. However, the strength of their impact varied. 
The reason for this lies in the fact, that entities of various sizes operate in 
different segments of the market, which can be distinguished within individual 
sectors. The company size turned out to be an important factor impacting the 



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financial results of US public companies in the years 1987–2006. In turn, im-
pact of the sector environment on the profitability of the examined entities was 
small (Lee, 2009). Also, Ruefli and Wiggins (2003) believe that the sector 
environment does not have any significant impact on enterprise performance. 
The authors emphasize that managers play a key role in formation of the fi-
nancial results and that it is primarily the financial situation of a company that 
determines its performance. Similar results were obtained by Stierwald 
(2010), who analyzed 961 large Australian enterprises in the years 1995–
2005. The author concluded that, in contrast to the internal factors, impact of 
the sectoral effect on the profitability of the analyzed entities was scant.  

The authors of the above-cited studies used the return on assets, and thus 
considered enterprise performance in accounting terms. In contrast, Ha-
wawini, Subramanian and Verdin (2003), applied measures based on enter-
prise value, i.e. the economic value added (EVA) and the market value added 
(MVA), in addition to the return on assets (ROA). The research carried out by 
these authors confirms that a given sector has significant impact on the finan-
cial results of the enterprises within it, while the strength of its impact is 
greater than that of the internal factors specific for individual entities. Only in 
the case of the enterprises operating as market leaders and those least compet-
itive within a given sector, a reverse relation was observed. For both groups 
of entities, the strength of the impact of internal factors was greater than that 
of the sectoral ones. 

Dragonić (2014) conducted the study on Croatian fast-growing small and 
medium businesses. The research showed that an impact of internal factors 
and sector on company’s profitability depends on the period, i.e. life cycle 
stage of a company and general state of the economy.   

Margaretha and Supartika (2016) examined internal factors affecting prof-
itability and industry affiliation of SMEs firm listed in Indonesia Stock Ex-
change. The results confirmed that firm size, growth, lagged profitability, 
productivity and industry affiliation significantly effect on profitability. The 
industry affiliation has a positive impact on profitability. The authors empha-
size that for further improve company’s performance the manager should de-
fine a strategy to increasing profitability with focusing on productivity and 
industry affiliation. 

Many other studies confirmed that industry affiliation influences com-
pany’s profitability ratio. For example, Vijayakumar (2011) concluded that 
vertical integration is significantly associated with profitability. The studies 
conducted by Salman and Yazdanfar (2012) and Yazdanfar (2013) indicate 
that firm industry affiliation has and impact on its profitability.  

The influence of internal factors on company’s performance was also an-
alyzed by many other authors. Tailab (2014) analyzed an impact of leverage, 



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DYNAMIC ECONOMETRIC MODELS 18 (2018) 115–127 

120 

liquidity, inventory, growth, size and firm’s age on financial performance of 
100 top non-financial American firms listed on Fortune 500 in 2009–2013. 
Alarussi and Alhaderi (2018) examined the internal factors affecting profita-
bility in Malaysian-listed companies. This study applies the resource-based 
theory. Research is based on five independent variables that were empirically 
examined for their relationship with profitability. The findings show a strong 
positive relationship between firm size, working capital, company efficiency 
and profitability. The results also show a negative relationship between lever-
age and profitability.  

In the available literature on the subject, few studies can be found regard-
ing the impact of the sector environment and the internal factors on the prof-
itability of Polish enterprises (Matyjas, 2012, 2016). The author analyzed 
companies listed on the Warsaw Stock Exchange. The research results vary, 
depending on the number of the subjects admitted to the sample and the period 
covered by the analysis. Thus, during the period of 2008–2011, 389 compa-
nies were examined. The author proved that internal factors played an im-
portant role in shaping those companies’ profitability. Sector environment, in 
turn, did not affect it (Matyjas, 2012). In further studies, the same author ob-
tained different results (Matyjas, 2016). This time, the subject of the analysis 
entailed 221 companies listed on the Warsaw Stock Exchange in the years 
2007–2012. It turned out that their profitability was impacted by both the in-
ternal factors and the sector environment. It should be noted, however, that 
the strength of the company-specific factors was, in this case, much higher 
than that of the sector-specific ones. 

3. The Research Sample and Description  
of the Research Method 
The subject of the analysis entails the companies listed on the main market 

of the Warsaw Stock Exchange in the years 1998–2016, as of 15 December 
2017. To select the entities, the sector classification used for the needs of the 
Warsaw Stock Exchange was applied to the sample. Out of 477 companies, 
companies from the following sectors and subsectors were accepted for the 
research: fuels and energy (14 companies); chemistry and raw materials 
(37 companies); construction (44 companies); electromechanical industry 
(24 companies); transport and logistics, business supplies and enterprise ser-
vices (20 companies in total); consumer goods (39 companies); wholesale 
trade, retail chains and e-commerce (13 companies in total); recreation and 
leisure, media and games (26 companies in total); health care (15 companies) 
and technologies (28 companies). Companies from the financial sector were 



Impact of the Sector and of Internal Factors on Profitability… 

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121 

excluded from the research. Therefore, 64 entities were rejected, with the ex-
ception of the enterprises included in the real-estate subsector (20 companies), 
which carry out property development activity, consisting in the construction 
of real estate and then its sale or rental. The sector, and more generally – the 
real estate market can be considered from two perspectives: the financial and 
the material one. In the first case, it should be perceived through the prism of 
the links with the financial capital market, while in the second – in terms of 
the real estate supply and demand (Wiśniewska, 2004, p.79). Due to the pre-
sumptions resulting from the second conceptualization, real estate develop-
ment companies were accepted for research. 

The sample excluded the entities that did not submit complete financial 
statements during the period under consideration, i.e. 52 enterprises. The com-
panies in bankruptcy or under restructuring, i.e. 15 enterprises, were also re-
jected. Moreover, only the entities that were continuously listed on the War-
saw Stock Exchange for a period of at least 5 years were admitted to the study. 
Therefore, 66 companies were excluded from the sample. Ultimately, 280 en-
terprises were qualified for the research, i.e. almost 59% of the pre-selected 
entities. 

To identify the impact of selected internal factors on the profitability of 
the examined companies and the dependence of profitability on the sectoral 
affiliation, estimation of an econometric model, in a panel approach, was pro-
posed. Due to the fact that not all companies were listed on the Warsaw Stock 
Exchange or operated since 1998, it was an unbalanced panel. 

A linear model of the dependence of the profitability level on the affilia-
tion to the sector and on the internal factors has the following form: 

𝑦"# = 𝛽& +(𝛽)𝑆)

++

),+

+ 𝛼+𝐿𝐴𝑉𝐸𝑅𝐴𝐺𝐸"# + 𝛼4𝐺𝑅𝑂𝑊𝑇𝐻"# + 𝛼9𝐿𝐼𝑄"#

+ 𝛼<𝑁𝐷𝑇𝑆"# + 𝛼?𝑆𝐼𝑍𝐸"# + 𝛼A𝑇𝐴𝑁𝐺"# + 𝜉"# 

where  is an endogenous variable representing the profitability of the i-th 
company in the period t. Profitability is defined by the relation of the profit to 
the total assets (ROA) or the ratio of the net profit to the total equity (ROE). 
The variables Sj are centered dummy variables, taking the value of one if it 
belongs to a given sector, zero in other cases. While identifying individual 
sectors, the following markings were adopted: the real estate sector (RES); the 
fuels and energy (FE); chemistry and raw materials (CRM); construction (C); 
electromechanical industry (EI); transport and logistics, business supplies and 
services for enterprises (TLS); consumer goods (CG); wholesale trade, retail 
chains and e-commerce (TREC); recreation and leisure, media and games 
(RM); health care (HC) and technologies (TE). 

ity



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DYNAMIC ECONOMETRIC MODELS 18 (2018) 115–127 

122 

Additionally, the remaining exogenous variables that represent the inter-
nal factors of companies are: 

LEVERAGE – debt, the total debt and total assets ratio; 
GROWTH – increase, a percentage change in sales revenues in relation to 

the previous year; 
LIQ – financial liquidity, the relation of current assets to current liabilities; 
NDTS – investment tax shield, the depreciation and total assets ratio; 
SIZE – size, natural logarithm from the value of total assets; 
TANG – the structure of assets, the ratio of fixed assets to the total assets. 

Symbols  are the structural parameters, while 
signifies the model’s random component. 

The proposed model was estimated using the least squares panel method 
(pooled model). Then, using the Wald test, it was checked whether estimation 
of a fixed effects would be correct. 

4. Research Results 
As already mentioned, the empirical analysis aims to indicate whether in-

ternal factors and sectoral affiliation determine the profitability level of an 
enterprise. The above-proposed model was estimated in a panel approach. 
While modeling the shaping of the ROA variable, the results of the estimations 
of the 4 versions of the model have been presented in Table 1. Model (1) in-
cludes the statistically significant variables. This means that an increase in the 
financial leverage, the financial liquidity, the non-debt tax shield and the size 
of an enterprise cause a decrease in the ROA, while an increase in the share 
of the fixed assets in the total assets, expressing the structure of assets, results 
in an increase in the ROA. 

The negative relationship between the financial leverage and the asset 
profitability is explained by the pecking order theory. The most profitable en-
terprises are in low debt due to the fact that they prefer internal financing first 
(they use their earned profits for this purpose), not because they ultimately set 
a low level of the debt ratio. In contrast, enterprises with low profitability are 
more willing to use debt, because they do not have sufficient resources from 
their internal sources. The tendencies described are supported by the studies 
on the capital structure of Polish enterprises, carried out by other authors 
(Marzec, 2010; Janus, 2006; Lisińska 2012; Barburski, 2014, Wrońska-
Bukalska, 2014; Jaworski and Czerwonka, 2017). 

The negative relationship between asset profitability of and financial li-
quidity is justified by the fact that purchase of inventories exceeding current 
needs generates additional costs, which do not bring additional revenues – it 
provides a hedge, in the event of a sudden increase in the demand or in the 

611110 ,...,,,...,, aabbb itx



Impact of the Sector and of Internal Factors on Profitability… 

DYNAMIC ECONOMETRIC MODELS 18 (2018) 115–127 

123 

prices of supplies and raw materials. On the other hand, current assets and 
therefore liquidity increase, while profitability does not. Asset profitability 
may even drop, because the value of assets increases, while profits may de-
crease, since excessive stocks create additional costs. 

Table 1.  Estimates of the linear regression model for ROA  

Variable 
Model 

(1) (2) (3) (4) 
pooled FE pooled FE 

const 2,4175*** 4,4642*** 2,5358*** 4,5556*** 
RES   –0,3417  
FE   0,3121**  

CRM   –0,0195  
C   –0,0858  
EI   –0,0646  

TLS   –0,3982***  
CG   0,0352  

TREC   –0,0365  
RM   0,2938*** 0,4461** 
HC   –0,1665 –0,7783*** 
TE   0,4717*** –1,0186*** 

LEVERAGE –0,1599*** –0,1531*** –0,1588*** –0,1536*** 
GROWTH   0,0000  

LIQ –0,0064** –0,0099*** –0,0059** –0,0105*** 
NDTS –37,7074*** –47,928*** –38,8988*** –47,6416*** 
SIZE –0,1476*** –0,2990*** –0,1574*** –0,3086*** 

TANG 2,9309*** 3,4679*** 3,0362*** 3,6041*** 
Joint significance test 3,7365# na 3,6960# na 
Breusch-Pagan test 376,6740# na 300,6340# na 

Hausman test 388,53538# na 429,5220# na 
Note:  **) ***) statistically significant at the significance levels 0.05 and 0.01 respectively; #) statistically 
significant at the significance level of 0.05. 

The non-debt tax shield – expressed as the ratio of the depreciation to the 
total assets, is a substitute for an interest tax shield. Enterprises collecting 
funds through depreciation do not have to involve debt in their investment 
financing. Therefore, entities that have the option of financing investments 
from internal sources, use a non-debt tax shield. However, making high de-
preciation charges applies only to modern components of the fixed assets, with 
a high initial value. Hence, if high-value modern fixed assets dominate in the 
structure of the company's assets, the value of the return on assets may be 
lower than in the entities that have efficient but used-up fixed assets. 

The negative relationship between the size of an enterprise and the profit-
ability of the assets can be justified by the fact that there are components 
within the asset structure that do not bring additional revenues over a short 
period of time, e.g. some long-term investments or stocks of raw materials and 



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DYNAMIC ECONOMETRIC MODELS 18 (2018) 115–127 

124 

supplies, providing security in the event of a sudden increase in the demand 
or in the prices of supplies and raw materials. In enterprises with a high share 
of such assets in the total assets, profitability may be low, because their value 
is high, while profits may be reduced, because a high level of non-production 
assets creates additional costs. 

The positive relationship between the structure of assets and the value of 
ROA should be explained by the significant share of the investments yielding 
a high rate of return in the asset structure of the companies under examination. 
It causes an increase in the profitability level of these entities.  

Model (1) indicates predominance of the fixed effects model, hence the 
version (2), which is an estimation of the model describing the impact of in-
ternal factors, which is the fixed effects one. Version (3) contains estimations 
of the model with sectoral effects and factors, using the pooled model. The 
final version (4) indicates the sectoral effects, statistically significant, and the 
internal factors of the fixed effects model. The results indicate in which sectors 
statistically significant differences in the ROA level were noted, while impact 
of individual factors on the ROA level was indicated (Table 1). 

Table 2.  Estimates of the linear regression model for ROE 

Variable 
Model 

(1) (2) (3) (4) 
pooled FE pooled FE 

const 0,2354 0,6781 2,5358*** 4,5556*** 
RES   –0,3417  
FE   0,3121**  

CRM   –0,0195  
C   –0,0858  
EI   –0,0646  

TLS   –0,3982***  
CG   0,0352  

TREC   –0,0365  
RM   0,2938*** 0,4461** 
HC   –0,1665 –0,7783*** 
TE   0,4717*** –1,0186*** 

LEVERAGE   –0,1588*** –0,1536*** 
GROWTH   0,0000  

LIQ   –0,0059** –0,0105*** 
NDTS 16,0422** 17,0020* –38,8988*** –47,6416*** 
SIZE   –0,1574*** –0,3086*** 

TANG 3,8527** –5,8666** 3,0362*** 3,6041*** 
Joint significance test 1,1625# na 3,6960# na 
Breusch-Pagan test 0,1408 na 300,6340# na 

Hausman test 0,4527 na 429,5220# na 
Note:  **) ***) statistically significant at the significance levels 0.05 and 0.01 respectively; #) statistically 
significant at the significance level of 0.05. 



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Next, a model was estimated by adopting the value of ROE as a determi-
nant of the profitability level. The results are presented in Table 2. Similarly, 
as in the case of the ROA, it was estimated in four versions. Generally, the 
results justify using the panel OLS method (pooled model), only the model in 
version (4) contains estimates with fixed effects (within group estimator). 
It can be noticed that the value of ROE statistically significantly differs in the 
consumer goods and services sectors, in the case of a model containing only 
sectoral effects. The significance of internal factors confirmed the results ob-
tained for the ROA index. 

Conclusions 
The empirical analysis carried out enabled indication of the dependence 

of the profitability level of companies on their sectoral affiliation and on se-
lected internal factors characterizing those companies. The model estimated 
for the ROA indicates a statistically significant level of this index, higher than 
the average in the service sector, and higher in the sectors of health care and 
technology. In addition, an increase in the financial leverage, financial liquid-
ity, non-debt tax shield and enterprise size cause a drop in the ROA. On the 
other hand, an increase in the value of the ratio of fixed assets to the total 
assets results in an increase in the ROA. Similar results were obtained for the 
models estimated for the ROE. Therefore, it can be concluded that there are 
no grounds to reject the hypothesis assumed in the introduction, about the 
profitability of companies listed on the Warsaw Stock Exchange being de-
pendent on their sectoral affiliation and on selected factors. In other words, 
profitability of the examined enterprises results from the decisions made by 
the managers and from the impact of the sector environment.   

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Wpływ sektora i czynników wewnętrznych na rentowność spółek no-
towanych na GPW w Warszawie  

Z a r y s  t r e ś c i. Celem artykułu jest ocena wpływu otoczenia sektorowego oraz wybranych 
czynników wewnętrznych na poziom rentowności spółek notowanych na GPW w Warszawie 
w latach 1998–2016. Wzrost dźwigni finansowej, płynności finansowej, nieodsetkowej tarczy 
podatkowej oraz wielkości przedsiębiorstwa powodują spadek ROA. Z kolei wzrost wskaźnika 
rzeczowych aktywów trwałych do aktywów ogółem powoduje wzrost ROA. Analogiczne wy-
niki otrzymano w przypadku modeli oszacowanych dla ROE. Oznacza to, że rentowność bada-
nych przedsiębiorstw jest wypadkową decyzji podejmowanych przez menedżerów i wpływu 
otoczenia sektorowego. 

S ł o w a  k l u c z o w e: rentowność aktywów ROA, rentowność kapitału ROE, efekt sekto-
rowy, estymacja panelowa. 


