Fuentes de vitamina D

This analysis is based on the microcensus (Mikrozensus) which is provided by the Federal Statistical Office. It is an official representative yearly household survey, similar to the Current Population Survey in the USA and the Labour Force Survey in the UK. The microcensus consists of a 1 % sample of all households in Germany, i.e. about 370,000 households per year, 70 % of which (selected at random) are available to researchers outside the Federal Statistical Office. The large sample size is important for this analysis since only about 1 % of the population belongs to the group of self -employed tradesmen with income above the relevant threshold. As the microce nsus is an official census, most questions are subject to compulsory response. This ensures a low rate of item non-response and that entrepreneurs, including those with high income, are adequately represented.24

I restrict the sample to individuals between 18 and 65 years of age and exclude s farmers, people in education, vocational training, or military service, and civil servants. The excluded individuals presumably have a limited occupational choice set, or at least they have different determinants of occupational choice that could distort the analysis. I also exclude family members helping in a family business because they are not entrepreneurs in the sense that they run their own business.

The analysis of self -employment rates is based on pooled cross sections of the microcensus from 1991 to 2001. I do not consider years before 1991 as this was the first year cove ring the five new federal states of eastern Germany. Furthermore, income information is given in categories, and 1991 is the first wave providing more detailed categories for high incomes. The reference week of the question for an individual’s employment status is always the last week in April. As mentioned in section 3.2, I decide not to include observations potentially influenced by the Tax Reduction Act 2000, which was passed in October 2000 and came into effect in January 2001. Taking into account that adjusting expectations and eventually changing occupation as a reaction to a reform would take some time, the employment state in April 2001 is probably not influenced much by the reform. Thus, I

24 _{More information about the microcensus can be found at}

http://www.destatis.de/jetspeed/portal/cms/Sites/destatis/Internet/EN/Content/Statistics/Mikrozensus/Aktuell.ps ml.

exclude the years 2002 and later. Since the microcensus was not carried out in 1992 and 1994, I cannot include these years in the analysis.

The first reform I analyse, the Location Preservation Act, was passed in September 1993 and came into effect on January 1st, 1994. Deliberation in parliament started on January 4th, 1993, when the first draft was issued. It is unlikely that agents adjusted their behaviour early during the ongoing debate because the outcome of the political process was uncertain.25 Thus, the employment state in April 1994 is probably not influenced by the reform, again considering the time lag before a reaction can be observed.26 In contrast, the employment status in April 1995 is potentially influenced by the reform. Thus, all observations from 1995 onward are marked by a “post 1994 reform” dummy. The second reform, the Tax Relief Act, was passed in March 1999 and went into effect in two steps, on January 1st, 1999 (retroactively) and January 1st, 2000. Parliamentary deliberation started with the first draft law on November 9t h, 1998. The employment status in April 1999 is unlikely to have been influenced by the reform which was passed only a month before. Thus, a “post 1999 reform” dummy is assigned to all observations in 2000 and 2001. For the joint estimation of the effects of the two reforms, I convert the “post 1994 reform” to a “post-1994, pre-1999 reform” dummy variable that is zero for all observations from 2000 onward to avoid an overlap of the two reform dummy variables.

An increasing (decreasing) self-employment rate can be caused by a higher (lower) entry rate, or a lower (higher) exit rate, or a combination of both. It is also possible that a higher (lower) entry rate is offset by a higher (lower) exit rate, and that the self-employment rate remains constant as a consequence. Additionally to analysing the probability of being self- employed, I thus also study the probability of entry into self -employment and exit from self- employment to gain insights into possible changes in the flows. As the microcensus provides independent cross sections, each person is observed in a single year t only. To identify trans itions between employment states, I rely on a retrospective question on a respondent’s employment state in the year prior to the interview. It was only posed in a 45 % sub-sample of the microcensus (selected at random), and only from 1996 onwards. The analysis of transitions can thus only be based on this sub-sample from 1996 to 2001, and I can therefore only analyse the second reform of 1999.

25

On June 22nd, the Bundesrat (Federal Council) denied its approval of the law. Consequently, the Mediation Committee between the Bundesrat and the Bundestag (parliament) was invoked, and the law was changed considerably during this process .

In principle, the set of transitions between self-employment and dependent employment includes those who decide to incorporate. An unincorporated firm is run by a self-employed sole proprietor or by various self-employed partners, whereas in an incorporated firm, which is a legal entity, the managers are employees.27 It is not clear, though, if all respondents make the distinction correctly when answering the survey question; many formerly self-employed will probably still report themselves as self-employed after incorporating. Thus, the effect of the tax reforms on self-employment may be underestimated.