Systems and methods are described for transforming actual aggregated data (e.g., transaction and terminal data) from a large number of POS terminals into market trend reports that include macro-level trend data and analyses. For example, POS datasets are aggregated from POS terminals distributed across many merchant outlet locations, each POS dataset including location data and transaction data for its respective POS terminal. A reporting request is received for a market trend report corresponding to a designated market over a designated timeframe. A market dataset is identified from the portion of the aggregated POS data corresponding to the designated timeframe and market. Unreliable portions of the data may be discarded. Market trend data is then calculated as a function of the reliable portion of the market dataset, and graphical report data is output as a function of the market trend data in response to the reporting request.