Financial crises in USA 2008 is seen as one of the worst crises in the last ninety years. Financial crises went hard on the American economy and abroad as a whole. Pressures under both administrations and rising house prices was one factor that led to the burst of house bubble in 2008. America has today eight financial institution seen as systemically important banks globally and holds a big market share in the US market. If one of these institution goes closer against bankruptcy, it can jeopardize the US and world economy as well. This thesis aims to analyze how the largest and systemically important investment banks operations could affect their distance from insolvency. With the data that is available, one has constructed and used a panel data to see and calculated Z-Score, with Z-Score as dependent and six independent variables over a time period of 17 years. In the panel regression the results show that comparing mean of Z-Score and predicted Z-Score, the values are similar and both follows a trend. This indicates that model used in thesis, belongs with Z-Score. The result showed that Z-Score for some banks were lower than normally under the financial crisis.