What’s the reason for the low growth relatively to other countries that are now in the same situation? To put another way, what’s the cause that differentiated Portugal from the other countries before the crisis of 2007-08, and how it faded since? Some recent papers and articles attempt to explain the causes of this relative weak performance, but although some of the causes advanced can in part explain the weak growth in Portugal, they do not fully explain the low growth relatively to the group mentioned above because many of the issues were also present in the other countries before the crisis.
Long term economic growth can be split into labor force growth and productivity growth. Invariably, the main cause cited for the Portuguese low growth has been productivity growth, or the lack of it, but although this certainly has been a problem in the last decade, not so much before, it hardly appears enough to explain the relative week performance. The differences in productivity gains don't seem big enough to justify the differences in GDP growth, even in the cases of Ireland and Greece, countries where productivity growth was higher than Portugal; but certainly this is true for Spain as its productivity growth was smaller than Portugal, as can be seen in the chart below. In the last decade, productivity growth in Portugal was threefold that of Spain but its growth was less than half.