Understanding Monte Carlo simulations for financial forecasting

A Monte Carlo simulation is a tool that helps us predict the future of your finances by running many different scenarios. Think of it like rolling a dice many times to see what might happen, but instead of rolling a dice, we use data about your portfolio, your goals, and the way markets typically behave.

What is a Monte Carlo Simulation?

At its core, a Monte Carlo simulation helps us understand the range of possible outcomes for your financial future. Instead of guessing exactly what will happen, it creates many different "what if" scenarios to show how your investments might grow or shrink over time. This helps you make better decisions about how to manage your money and plan for the future.

How Does It Work?

1. Running Multiple Simulations: We run 1,000 different simulations. Each one uses a random set of assumptions about things like how your investments will perform to give us a wide range of possible outcomes.
   
   
2. Using Your Data: The simulation starts with the portfolio growth rate you’ve defined and incorporates a normal distribution to account for potential fluctuations in returns. By applying a standard deviation, we simulate a range of possible outcomes, allowing for both higher and lower-than-expected growth. This process runs multiple scenarios to help illustrate the variability and risk of your portfolio’s performance.
   
   
3. In Today’s Dollars vs. Real Dollars: We offer two ways of running the simulation:
   
   
   • In today’s dollars: This shows your future financial outcome without adjusting for inflation. It's a snapshot of your growth, showing what the dollar amount would be today.
     
     

In real dollars: This takes inflation into account. It shows how your money will grow after adjusting for the rising cost of living. This can help you see how much your investments will actually be worth in the future, taking into consideration how inflation impacts purchasing power.

How do we define “Success”?

In our Monte Carlo simulations, we define success in a few ways:

1. Positive Net Worth: If the final result of the simulation shows a positive net worth (meaning your total assets are greater than your debts), then the simulation is considered successful.
   
   
2. Meeting Your Target: If you’ve set a goal, such as a target net worth (e.g., $1,000,000) or a legacy you want to leave to your loved ones, success is defined by whether the simulation ends with you reaching that goal.

However, there are some cases where a simulation could have a positive net worth but still not be considered fully successful. For example:

• Negative Cash Flow: If your portfolio grows, but your spending exceeds your income for a long period of time (negative cash flow), the simulation will end with an "N/A" score. This means that while your investments might look like they are growing, the scenario would not be sustainable in real life because you wouldn't be able to maintain a negative cash flow. This is something we want you to be aware of to ensure your plans are realistic.

What Does "Chances of Success" Mean?

In a Monte Carlo simulation, chances of success refer to the likelihood that your financial plan will meet your goals based on the simulated outcomes. It is the percentage of simulations where your portfolio ends with a positive net worth or reaches a predefined target (e.g., $1,000,000).

For example, if your forecast shows a 78% chance of success, it means that, out of 1,000 simulations, 780 of them resulted in your portfolio meeting or exceeding your goals, while 220 simulations did not. This gives you an idea of how likely it is that your financial plan will succeed based on the assumptions and scenarios used in the simulation. A higher percentage indicates a greater likelihood of success, while a lower percentage suggests more risk or uncertainty about reaching your goals.

Why Does the Rate of Return Matter?

The rate of return is an important part of the simulation. This is the average growth rate you expect your investments to achieve. In our simulation, we take the growth rate you’ve provided and use something called a normal standard deviation distribution. This allows us to show a range of possible returns. Sometimes your investments will do better than expected, and sometimes they may perform worse. The simulation includes all of these possibilities to give you a clearer picture of your future financial outlook.

Considering a Partner's Future

If you're running a partner simulation, the analysis takes into account the financial situation after the second partner’s passing. This helps ensure that the simulation reflects the ongoing financial needs and goals of both individuals in the partnership.

Why Monte Carlo Simulations Are Important

Monte Carlo simulations give you a deeper understanding of the uncertainties in your financial future. By running thousands of simulations with different assumptions, we can show you a range of possible outcomes, not just one predicted result. This helps you see where your financial plan could succeed or fail, so you can make smarter decisions about saving, spending, and investing.

Whether you’re planning for your retirement, a big purchase, or a legacy to leave behind, Monte Carlo simulations can help you understand the likelihood of success and the factors that could influence it. It’s like preparing for many possible futures, so you’re ready for whatever comes your way.