education ranges from no education to some education not including a high school degree. The
education recoding uses the 1997 International Standard Classification of Education from the
United Nations Educational, Scientific and Cultural Organization; the LIS believes this recode to
produce an education variable that is as comparable across countries as possible. For this paper, I
only include countries for which a reclassification is available; some countries were not able to
be recoded.8
In the LIS data, each country/year observation is a separate dataset; thus, to avoid
possible inconsistencies between countries I do not merge the datasets. Therefore, for each
country/year observation, I sort individuals by education level; each observation in my dataset is
a specific country, year and education level. Any individual characteristics, therefore, are the
mean value of that characteristic across education level within a given country and year.
For each observation, I am interested in the mean annual gross wage of individuals within
skill.9 Unfortunately, gross income is only available for approximately half of the countries; the
remaining countries have income provided as net. In order to maintain a sample size large
enough for statistical inference, I transform the average net income by education level into
average gross income by education level using each country’s tax code for the specified year.10 I
obtain countries’ tax codes from Individual Taxes: A Worldwide Summary. My calculation takes
into account national income tax, local income tax, and the employees’ contribution to social
security. Table 1 lists the countries and years included in my data and indicates those countries
for which net income has been transformed into gross income.11 Figure 1 shows the average
gross wage by education level for France, Denmark and Greece. As expected, higher levels of
education always result in a higher wage. Gross wages by education, marginal corporate tax rates
and openness measures for all countries in 1994/1995 are displayed in Figure 2.
12