We conducted a quantitative analysis to determine how the prerequisite path of students taking calculus I impacts their grade performance. We began by investigating the performance of students that took college algebra and trigonometry versus those that took pre-calculus ahead of their credit-bearing calculus I attempt. We concluded that there was a significant difference between the two prerequisite routes. We then performed regression analysis to view the number of credit prerequisite credit hours, including multiple attempts, as a predictor of calculus I GPA and A-proportion. We found a strong negative correlation between these variables. We hope this study can be replicated at other institutions and in other fields to help university policymakers with decision-making regarding course listings.