Dataset used for the case study in the MSc thesis "Robust fleet planning under stochastic demand" and in the OMEGA journal article "Portfolio-based airline fleet planning under stochastic demand". The dataset contains: - historical passenger data extracted from the TranStats database of the Bureau of Transportation Statistics (BTS/US DOT). The underlying dataset that was used is the T-100 Domestic Market (U.S. Carriers) data table that contains monthly scheduled US domestic passenger data based on a 10 percent ticket sale information dataset, aggregated for all airlines for the period 1990-2014. - estimated parameters, per market, for the the mean reverting Ornstein-Uhlenbeck process. - model parameters used in the optimisation model, including aircraft features. - computed aggregated transition probabilities used in the discrete-time Markov Chain in the scenario generation model. - BTS/US DOT fare data from 2014.