$1\mathrm{.}2$ The case study mentions that a European bank reduced forecast error by $40\%$ and improved productivity by $30-50\%$ by implementing a new forecasting system. Consider a similar situation in a hospital emergency room $($ER$)$ that struggles with fluctuating patient arrival rates. What specific types of data would be critical for forecasting patient arrival rates and optimizing staffing levels? $(5$ Marks$)$