Broker Check

Quick Math

January 13, 2021
Share |

Don’t have a calculator handy, but need a quick answer to a financial question? Here are three shortcuts:

  • How long will it take to double your money? Divide 72 by your annual investment return. If you are earning 8% annually on your investments, it takes nine years for your investments to double in value.
  • How much does it cost to purchase an item before taxes? Multiply the cost by 1.7 if you are in the 35% or 33% marginal tax bracket, 1.6 in the 28% tax bracket, 1.5 in the 25% tax bracket, 1.3% in the 15% tax bracket, and 1.2 in the 10% tax bracket. These numbers also factor in Social Security and Medicare taxes, but not state income taxes. So, if you are in the 28% marginal tax bracket and want to spend $10,000 on a vacation, it will cost $16,000 before taxes.
  • How much will your retirement savings grow in 30 years? Assuming an 8% investment rate of return, add a zero to the amount. Thus, if you have $100,000 today, it could grow to $1,000,000 in 30 years. This is a handy way to look at whether it’s worth spending money on something. For instance, the $25,000 you spend on a car today could be worth $250,000 in 30 years.


Randall Wealth Management Group and Vanderbilt Financial Group are separate and unaffiliated entities.
Vanderbilt Financial Group is the marketing name for Vanderbilt Securities, LLC and its affiliates. Securities offered through Vanderbilt Securities, LLC. Member FINRA, SIPC. Registered with MSRB. Clearing agent: Fidelity Clearing & Custody Solutions Advisory Services offered through Consolidated Portfolio Review Clearing agents: Fidelity Clearing & Custody Solutions, Charles Schwab & TD Ameritrade Insurance Services offered through Vanderbilt Insurance and other agencies Supervising Office: 125 Froehlich Farm Blvd, Woodbury, NY 11797 • 631-845-5100 For additional information on services, disclosures, fees, and conflicts of interest, please visit

This newsletter was prepared by Integrated Concepts Group, Inc. The opinions expressed in this newsletter are for general information only and are not intended to provide specific investment advice or recommendations for any individual. It is suggested that you consult your financial professional, attorney, or tax advisor with regard to your individual situation. The views expressed are those of the author and may not necessarily reflect those held by Randall Wealth Management Group or Vanderbilt Financial Group. Material presented is believed to be from reliable sources and PSEC makes no representation as to its accuracy or completeness.