Bulgaria ranks 66th among 185 countries in the World Bank's Doing Business report for 2013.
Last year Bulgaria occupied the 59th position among 183 entries in the same ranking.
Starting business in Bulgaria became more difficult over the past year, as the country dropped to the 57th from the 49th spot in this department, the report said.
Conditions for getting a construction permit, obtaining connection to the electricity grid and making tax payments in the Southeast European country also deteriorated.
Greece was among the 10 economies that improved the most over the past year, climbing up to the 78th spot in the overall ranking from the 100th position it held a year earlier.
It improved its regulatory environment at a greater pace in the past year than in any of the previous six ones. The Mediterranean country made sharp progress in streamlining the process of granting construction permits and strengthening investor protection.
In the 10th edition of the Doing Business report, Singapore maintained its top spot, while Poland was the country, which improved the most.