Model-Based Development (MBD) is widely used for embedded controls development, with MATLAB Simulink being one of the most used environments in the automotive industry. Simulink models are the primary design artifact, and as with all software, must be constantly maintained and evolved over their lifetime. It is necessary to develop models that support likely changes in order to assist with evolution/maintenance processes. In order to do so, the types of frequently performed changes must be understood, and appropriate language mechanisms must be available to support these changes. However, Simulink model changes are currently not well understood. We analyze a real industrial software repository of our industrial partner and its version control system to provide insights into the likely changes for Simulink. The intent with this analysis includes providing guidance on how Simulink is used in industrial practice, and how particular model changes can impact system evolution.