Within the framework of micro backward looking methodology, we propose and compute an effective overall tax rate for Bucharest Stock Exchange traded companies for 2000 – 2009 period. We tried to capture all public finance liabilities that a company has to cope with as a share of turnover, no matter if they are related to capital or labour, or if they are included or not in the production costs. Therefore, we propose the concept of corporate effective overall tax rate and we make some calculations using detailed data from companies’ financial reports. We show that effective overall tax rate have constantly decrease throughout the period surveyed, except for the year 2009, when the economic crisis took its toll from the companies turnover, thus making the effective tax rate to increase. Second, although the effective tax rate due to social security contributions decreased during the period, the share attributable to social security contributions in the overall tax rate increased, mainly due to the corporate income tax rate cut. Third, the tax burden generated by other significant taxes (mainly local taxes) is generally bigger than initially thought. In fact, we show that, among all public finance liabilities, corporate income tax has the lowest share of turnover for Bucharest Stock exchange traded companies.