The purpose of this thesis is to identify key factors underlying exchange rate developments during the European sovereign debt crisis by examining the impact of credit rating news, published by the three leading credit rating agencies, on conditional returns and volatility of EUR/USD (direct quotation) exchange rate. Empirical results highlight the importance of interest rate differential and volatility index of options exchange in explaining EUR/USD exchange rate volatilities. Downgrade announcements by Standard & Poor’s as well as watch revisions by Fitch Ratings had a detrimental impact on the value of Euro, leading to a subsequent Euro depreciation over the period under consideration (January 2009 – April 2012).

In context of czech membership in the Europen Union we always discuss the question if the acceptance of the euro as official currency is for our country and czech companies beneficial or not. The aim of this thesis is to describe microeconomic benefits of join the euro for company TECHO, a.s. that I have been working for over two years. TECHO, a.s. is an important provider of comprehensive services for the furnishing of commercial interiors in the Czech republic and its products are available on three continents -- Europe, Asia and Africa. Because of this fact is the question of acceptance or non-acceptance of the euro for this company very important and actual. The method of research is the analysis of exchange rates that I apply on economic results of the firm for years 2005-2009. The analysis should answer the question if the acceptance of the euro is for the firm TECHO, a.s. profitable or not.