Abnormal Return Calculator (ARC)

ARC is a free, browser-based abnormal return calculator for event studies. Upload your firm and market data, choose an expected-return model (market model, market-adjusted, CAPM, Fama-French 3, 4, or 5 factor, or constant mean), set your estimation and event windows, and ARC returns abnormal returns (AR), cumulative and average abnormal returns (CAR, AAR, CAAR), and 16 significance tests including Patell Z, the Kolari-Pynnonen adjusted tests, BMP, and the Corrado rank test. No licence, no login, no SAS or CRSP subscription. See the step-by-step instructions, a worked example, the AR, CAR and CAAR formulas, run it from R, or read the methodology hub.