This thesis deals with the determination of the effects of utilization of production capacity according to methodologies Czech accounting legislation and IFRS on the value of inventory and on the Company's earnings. The theoretical part deals with the definition of stocks from the perspectives of Czech accounting legislation and also in terms of IFRS. In this part there are also methods of allocating overhead costs, because of the close ties to the valuation of inventory. The practical part uses the knowledge gained from the theoretical part on data of actual production and the gained results are evaluated.