A further analysis (García-Teruel and Martínez-Solano, 2007) differs, however, in to the
number of days accounts payable: the relationship loses significance when controlling for
the possibility of endogeneity.
In order to provide empirical evidence on the effects of working capital management
on profitability of Portuguese SMEs, a study using the methodology of panel data, over
a sample of 6,063 SMEs in the time period 2002-2009 was conducted.
Results indicate that a reduction on the inventories held and in the number of days
that firms take to settle their commercial liabilities and to collect payments from its
customers, are associated to higher corporate profitability, and a similar outcome
occurs by reducing their cash conversion cycle. However, when controlled for possible
effects of endogeneity, the variable number of days accounts receivable shows a
positive relationship, which suggests the possibility of a conflict of influences between
corporate profitability and the credit that firms provide to customers.
The consensus that SMEs hold relevance in the development of its national economy
and the lack of studies of this type for the case of Portuguese SMEs, support the
relevance of the present study.
This research paper is organized as follows: the present section describes the
motivation of the study and presents the theoretical foundations, Section 2 describes
the research design and Section 3 presents the empirical results. Finally, the overall
findings and conclusions are summarized in Section 4.
2. Research design
In what follows data and variables used are presented and, estimation procedures
described. Finally, a statistical characterization of the sample is presented.
2.1 Data
This study utilizes a data panel of non-financial Portuguese SMEs. The data were
obtained from the SABI database (Iberian Balance Sheets Analysis System) for
an eight years period (2002-2009). This database was developed by the Bureau Van
Dijk and contains accounting and financial information for more than 350,000
Portuguese firms.
The selection of SMEs was carried out according to the requirements established by
the European Commission’s recommendation 2003/361/CE, May 6, on the definition of
SMEs. Companies that meet the following requirements for at least five of the eight
years under consideration were selected: fewer than 250 employees and turnover below
€50 million or total annual balance sheet below €43 million.
In addition to these selection criteria, several filters were applied, eliminating
companies with incomplete data in the time period under examination or no operating
activity. Given their specific accounting procedure, companies in the financial sector
were not considered. Finally, companies that had, for several variables, 1 percent of the
extreme values were eliminated. As a result of the application of these filters, the final
sample consisted of 6,063 companies.
2.2 Variables
For this analysis, the return on assets (ROA) was used as the dependent variable.
The independent variables are divided into two groups. The first considers the
variables related to the management of working capital and a second that includes
control variables.