A history of Compounding Interest

Peter Mullin • June 21, 2018

A history of Compounding Interest:

An Innovative Investment Idea


Compounding return .

It was an idea from Babylonian times … or earlier. It started with agriculture. The word ‘interest’ in multiple languages can translate to livestock. Specifically, it can refer to giving birth, or the multiplication of livestock (Source - 2).

In a Biblical parable, a master gives three servants the same amount of coins. Two come back with more than they received. The third servant buries his coins in the ground. The third servant says, “I was afraid I would lose your money, so I hid it in the earth. Look, here is your money back.” (Matthew 25:15)

The master tells this third servant, “Why didn’t you deposit my money in the bank? At least I could have gotten some interest on it.”

I think compounding interest is one of the most innovative financial ideas we have. The pursuit of a compounding rate of return is a part of many financial planning scenarios.

Compounding interest has been around for centuries. And over time it can have a positive impact on your wealth.

Here is how compounding interest can show up in your long-haul portfolio results.

Start by investing $10,000. Invest $500 every month for the next 240 months (20 years). Assume you receive 6% annually.

You will have invested $130,000 of your money. Like two of the servants in the Biblical parable, you realize a return on your capital. You could have about $259,894. Using the 4% Retirement Income Rule , you could have about $867/month to spend in retirement.


1 - Homer, Sidney and Richard Sylla. A History of Interest Rates . 1991. New Brunswick: Rutgers University Press.

2 - Goetzmann, WIlliam. Financing Civilization


These are hypothetical examples and are not representative of any specific situation. Your results will vary. The hypothetical rates of return used do not reflect the deduction of fees and charges inherent to investing.

The opinions voiced in this material are for general information only and are not intended to provide specific advice or recommendations for any individual.

All investing involves risk including loss of principal. No strategy assures success or protects against loss.

Peter Mullin is a Registered Representative with LPL Financial.

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Iran Watch: My best advice in a manic market

By Peter Mullin • March 4, 2026
My best advice a manic market By Peter Mullin, CEO/Financial Consultant Clients, we have never been in it for last year's results. Instead, we are betting on future prospects. We know life is not perfect. But over time, it will be okay. There are life lessons we can draw on from investing. One lesson involves taking bad periods with a grain of salt. Uncertainty is the price we pay for an investment’s potential rewards. Iran is striking back at the Middle East and allies like a multi-headed medusa. This did just occur in June of 2025. The difference is there is a presumed push for a regime change. It is a nail biting time, once again. My best advice is to keep the long view in mind during times that test our wits. But there is war. There is hyperinflation. This market is out of control. I can't lose anymore…I won’t live long enough to recover. How long has it taken a market to bounce back? Surprisingly, markets bounce back quite quickly from the real terror of missiles, mortars and military strikes. JP Morgan’s chart shows that it takes 2-3 weeks (or less) on average. The average drawdown is about -5.3%.

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Kristian Kerr | Head of Macro Strategy Last Updated: March 02, 2026 Over the weekend, the United States and Israel conducted a coordinated series of missile and drone strikes against Iran, targeting several high-value military installations in an effort to hinder Iran’s nuclear development efforts. These operations resulted in the death of Iran’s Supreme Leader, Ayatollah Ali Khamenei, marking a significant escalation and immediately heightening regional tensions. Iran quickly retaliated by launching a broad series of missile attacks directed not only at Israel but also at multiple Gulf states, including Qatar, the United Arab Emirates, and Bahrain. The repercussions were felt across the region. Several Gulf countries responded by shutting down their airspace and closing their equity markets. The conflict also affected global energy flows. Tanker traffic through the Strait of Hormuz, a vital waterway that carries about 20% of the world’s oil supply, came to a near standstill as shipping companies diverted vessels away from the area for safety reasons. Plus, Qatar shuttered liquefied natural gas production at the world’s largest export facility after being targeted by an Iranian drone strike. President Donald Trump stated that U.S. strikes on Iran would continue, signaling that tensions are likely to remain elevated for the next few weeks. From a market perspective, the energy market is the primary way through which this crisis is likely to impact global markets. Any sustained disruption to oil or natural gas flows, especially if both severe and long lasting, have the potential to influence inflation expectations, weigh on business confidence, and elevate volatility across asset classes. In simple terms, the more intense and prolonged the geopolitical shock, the larger the likely market impact. This pattern was already evident when markets opened on Monday. Brent crude, the global benchmark for oil prices, briefly touched $82 per barrel as traders responded to the possibility of tighter supply conditions. A sustained period of elevated prices would place upward pressure on inflation expectations, and that in turn could have broader consequences for both equity and interest rate markets. However, for such a persistent rise in crude prices to materialize, markets would likely need evidence of a more prolonged or even total shutdown of the Strait of Hormuz. A disruption of that scale would represent a meaningful escalation relative to what has occurred so far and would justify a more substantial risk premium in energy markets. There is also a political dimension tied to Iran’s internal stability, particularly regarding how the Islamic Revolutionary Guard Corps (IRGC) chooses to respond. Whether it opts to pull back or escalate further will play a major role in determining how much of the current shock reflects elevated risk premiums versus a true disruption to physical supply.  Oil Prices Spike as Strait of Hormuz Tanker Traffic Stalls

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One more speed bump before year-end?

By Peter Mullin • November 11, 2025
“Optimism sounds like a sales pitch. Pessimism sounds like someone trying to help you .” Morgan Housel, The Psychology of Money I do believe parts of the stock market are due for a reality check. But our big-picture, combined with our investment process says to hang in there. Connect with us now, especially if anything has changed for you. Remember April and Tariff Tantrums? Portfolio risk still matters Does is feel like stocks have done better than they actually have this year? Last year was a bumper year. And this year many have likely already forgotten the sharp April tariff tantrums. In recent history, market reality checks have been brief. For example, COVID caused stock markets to drop aggressively, followed by a wild recovery. Then 2022 reminded investors that taking imprudent risk can burn you. This rapid cycle of loss and recoveries makes it easier to get complacent. Yet, historical patterns suggest this isn't the time to ignore risk. It's easy to take on more risk after enjoying strong returns. But this can be dangerous—history doesn’t repeat, but it often rhymes. Let’s talk portfolio risk; risk can = rewards; but at what price? Let’s take a humble breath. Recall the math and logic of portfolio losses. Bigger portfolio risks require a higher pain tolerance. Large portfolio losses are hard to recover from. If a $100,000 portfolio loses 20%, it drops to $80,000. To get back to even requires a 25% return on your $80,000.  It’s easy to take on more and more risk when we are being rewarded. But many experienced retirees know, “easy come, easy go.”

LPL Research Presents 2025 Midyear Outlook

By Peter Mullin • October 8, 2025
We're pleased to offer 2025 Midyear Outlook: Pragmatic Optimism, Measured Expectations, providing a comprehensive recap of the economy and market to date, plus a forecast through year-end.

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Well it’s the end of the year. I just searched on Google for “market outlook 2018.” I came up with a little over 58-million “results.”

So should you be investing in stocks in 2018? The quick answer: It’s likely a prudent part of your portfolio. But it depends on your circumstances, right?

It’s apparently popular to throw your hat in the ring.

A mantra that you hear among disciplined professionals is to “stay the course.”

Then you hear “sell high, buy low.”

Who’s right?

The relief of a disciplined strategy is that it can be tailored to you. And tailor we think you should.

Yes, it’s possible that an investor may not utilize stocks in their portfolio at all. Or you may decide to go “all in” with a diversified stock portfolio.

(Side effects from tailoring a strategy may include increased confidence & persistence, apathy toward daily market reports, and increased focus on what really matters.)

Let’s begin with the “Why” of investing for you. Then you can request 15-minutes on the phone discuss your “how.”

So “Why Should You Invest”

Life changes and our “why” of investing ought to transform with life. Some invest for sport  – they like the risk/reward of investing – they’re in it for the thrill. I don’t hang with this crowd.

Most of us ought to invest for things we want. Our money & our goals are serious. By investing in a diversified portfolio we can pursue things we want.

1. Living A Comfortable Retirement: Retirement is a noun. It’s up to you to really design and live a retirement that reflects you.

2. Purchasing a Home: Home is a place to live. It can take a down payment.

3. Passing an Inheritance on to Family:

4. Student Loan Shield: This idea is important for many Millennial graduates. Student loans can dominate your budget. But instead of accelerating those payments, what if you paid your required payments, and then invested the additional money that you were going to pay against your loan balance?

5. Emergency Reserves: You probably have read that it’s prudent to keep a relative healthy amount of cash in your checking/savings. Once you’ve achieved that, then you can consider investing additional funds. Go a step further and consider a non-retirement account for you and your house. You can spend this on cars, vacations or use it just as described in #4.

The Dow Jones has seen positive results, so far, in 2017. It’s unusual and sort of uncomfortable as the independent financial advisor. Why is it uncomfortable?

What would sting & linger longer? Finding $20 in the parking lot? Or finding a $20 parking fine on your windshield?

We’ve been finding a lot of metaphorical “$20’s” (i.e. “positive results”) in our portfolios this year. So the second we find a parking fine (or a few in a row) we’ll be sure to ask if stocks are still the right place to park our money.

Complacency can work against us, Dear Clients. Just keep recalling your long-haul strategy and your “why” of investing.

***

Peter Mullin is an independent financial advisor registered through LPL Financial. He lives in Rogers, MN with his family. He was born and raised in St. Cloud, MN. Mullin Wealth Management is located in Waite Park, MN.

The opinions voiced in this material are for general information only and are not intended to provide specific advice or recommendations for any individual.

Investing involves risk including loss of principal.

There is no guarantee that a diversified portfolio will enhance overall returns or outperform a non-diversified portfolio. Diversification does not protect against market risk.

All performance referenced is historical and is no guarantee of future results.

All indices are unmanaged and may not be invested into directly. No strategy assures success or protects against loss.

 

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