Business Intelligence (BI) has become an essential part of the modern enterprise, and what used to be thought of as a luxury is now a matter of survival. Recent economic developments have forced companies to rethink their IT investment strategy. BI investments are now targeting the majority of people in the organisation instead of a select few. Thus, it is important to understand why users of a BI system choose to accept and use the system. Previous research has established the Technology Acceptance Model (TAM) as one of the most powerful and parsimonious models explaining user acceptance and usage behaviour of information technologies. This quantitative study replicates the original TAM study with the purpose to increase the understanding of BI usage, and investigates the behaviour of the users of the BI system QlikView in the case company GE Healthcare. The results showed a lower explanatory power for the model when compared to previous research. This indicates that how useful a user perceives a BI system to be does not affect the amount of usage to the same extent as predicted by TAM. Possible causes for this are discussed, with an emphasis on the influence of what tasks a user is confronted with and the measurement of system use.