Portfolio Simulation simulates investment portfolios and assess purchasing power by using the initial margin rate (IM) data from the marginable securities list as of the date of your evaluation also, calculating the securities value according to the closing price on the previous business day. Therefore, the purchasing power shown above is only an estimation. The actual purchasing power you will receive will vary depending on the initial margin rate and the stock value which depend on the date you make the security deposit and/or place an order which is different from the purchasing power calculated above.