This study investigates to what level private Nordic investors allocate capital to different types of assets, a phenomenon known as diversification. Additionally, it examines if the degree of diversification influences the investor’s economic welfare. To carry out this study, the authors of this paper took part of data containing information about 80,000 Nordic investors and their investments. This data was processed by a computer program to create a cross-sectional data set, enabling the authors to make conclusions about the average Nordic investor. The study shows that private Nordic investors succeed in their ability to diversify with respect to the total number of stocks, but that their investment choices cause their investments to be inefficient. The investor holds stocks highly correlated to one another, resulting in economic costs.