Abstract: Techniques are provided for adjusting a portfolio of financial assets in order to properly track the performance of a desired index. The techniques generally involve calculating a correlative value for the portfolio, and obtaining a correlative value for the index, relative to each of a number of different factors having data values that are likely to be correlated with an aggregate market value for the portfolio, where the correlative value for an item relative to a given factor is a measure of a tendency of the aggregate market value of the item to change based on a change in the data value for such factor (e.g., in the nature of a sensitivity or elasticity). Then, the portfolio is adjusted in an attempt to move its correlative profile closer to the correlative profile of the index.