A planning engine for a financial planning system including at least one processor is provided. The at least one processor is programmed to receive user profile data and account data, assign an asset class weight to each of a plurality of asset classes associated with the account data, and retrieve an expected asset class return, an asset class standard deviation, and an asset class covariance. The processor is also programmed to generate a portfolio data object for each of the plurality of future years wherein the portfolio data object calculates (i) an expected portfolio return across the plurality of asset classes and (ii) a portfolio standard deviation across the plurality of asset classes. The processor is further configured to pass the portfolio data object to a monte carlo return object, receive, from the monte carlo return object, a matrix, and return an account projection derived from the matrix.