PF Investing Club: The Stock Market & Compounding Interest

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In summary, the stock market has the potential to provide a 10% average rate of return, but there is risk involved. It is important to do your research before investing. Low cost index funds are a simple and diversified way to reduce risk.
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This thread was spawned off
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Do not act on any financial advice here before doing due diligence and meeting with a qualified financial advisor.

russ_watters said:
The stock market. It isn't called "interest", but the principle is the same.
hmmm I guess I am missing something. If I buy 1 share for $10 and if over a few years it goes up by 10% then I have $11. Where is the compounding?
 
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  • #2
So let's take a look at that. The worst decade for stocks was 1928-1938, with an annual return of -1.3%. This is the only 10-year period in the history of the Dow where the return was negative. The worst 20-year period (1928-1948) had an annual return of 2.5%. The worst 35-year period (1906-1941) had an annual return of 6.1%. The worst 50-year period was (1928-1978) had an annual return of 6.8%.

So the risk you have with buying stocks, and as you see, there is risk, is reduced the longer you own it. Furthermore, most people don't buy stocks all at once and hold them for decades. They buy continuously. That also reduces risk - when stocks go down, you buy more shares for the same money, and when they go back up, you realize more gains because you have more shares. This goes by the name of dollar cost averaging. It also shows that stocks are risky if you need the money a year or two down the road.

Low cost index funds, with dividend reinvestment (the equivalent of compound interest for an instrument that doesn't exactly produce interest), are a simple and diversified way to take advantage of this. Vanguard 500, for example, mirrors the S&P 500 for an expense ratio of 0.14% - that is, you need to drop those rates of return by 0.14% to cover the fees. So 6.1% becomes 5.96%. This particular fund has an initial investment requirement of $3000. This may seem like a lot, but if you don't have $3000, your first priority should be to beef up your savings. You need a safety net now more than you need returns down the road.
 
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  • #3
Greg Bernhardt said:
Where is the compounding?

The stock likely paid dividends. If you reinvest them, there's your compounding.
 
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  • #4
Greg Bernhardt said:
hmmm I guess I am missing something. If I buy 1 share for $10 and if over a few years it goes up by 10% then I have $11. Where is the compounding?
The $11 is your new principal and the growth is calculated against that new principal annually. You don't gain 8% of your original investment per year, you gain 8% of your current principal per year.
 
  • #5
russ_watters said:
The $11 is your new principal and the growth is calculated against that new principal annually. You don't gain 8% of your original investment per year, you gain 8% of your current principal per year.
Are we talking the market as a whole or for individual stocks? Looking at my positions with the stocks I own I don't see this as the case. Perhaps I should just go into the Vanguard 500 where I'll be given 6-8% on average and then see compounding.
 
  • #6
Greg Bernhardt said:
Are we talking the market as a whole or for individual stocks? Looking at my positions with the stocks I own I don't see this as the case. Perhaps I should just go into the Vanguard 500 where I'll be given 6-8% on average and then see compounding.
As a whole (S&P 500 is good), the average is about 8%. As V50 said, the WORST it has ever done over a retirement account span of time (50yrs) is 7% per year.
 
  • #7
Amazon and Google are obviously giants, but they now have extremely steep prices. Would they still be a buy if you are looking at holding them for 20-30 years? Or is it better to play completely safe and throw everything into Vanguard 500? So hold tech giants for 30 years or Van500?
 
  • #8
russ_watters said:
the WORST it has ever done over a retirement account span of time (50yrs) is 7% per year.

But the best (1949-1999) is only 12.8%. Long period investing reduces the risk of losing your shirt, but it also reduces the chances of a windfall. Something called a diversification return (analyzed in some detail by physicist Scott Willenbrock) helps with this.

Greg, the way this "compounding" works is suppose you bought your stock at $10. The next year it's at $9, the year after that, $12. Then $11, and so on, and after 20 years it's at $67. That works out to a 10% average rate of return because (1+10%)^20 = 67/10. It's an equivalent compound interest for an instrument that doesn't really have interest. There is an expectation that this will happen at some level for a profitable corporation. The company either pays a dividend, which you then reinvest (like compound interest) or the company re-invests the profit within the company, which is essentially the same as a reinvested dividend.
 
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  • #9
Vanadium 50 said:
The company either pays a dividend, which you then reinvest (like compound interest) or the company re-invests the profit within the company, which is essentially the same as a reinvested dividend.
Interesting! That makes sense to me, thanks! So, in a way growth stocks are riskier because you are betting they use your "dividend" wisely.
 
  • #10
Greg Bernhardt said:
So hold tech giants for 30 years or Van500?

Most of Amazon and Google's growth has already happened, so you shouldn't expect historical returns from them. Putting money in only two companies has inherent risk to it - there were times when WorldCom, Enron and WaMu looked like great deals (and Theranos would have too, had they been public). Now, not so much. What you would really like to do is to have invested in Amazon or Google when they were smaller. Can't do that, but maybe you can do that for the next Amazon.

One way to attempt that is to invest in smaller cap stocks, for example, the Russell 2000 index. The idea is that before Google was a big company, it was a small company, so investing in many small companies is a way to capture some of this growth, and by investing in many reduces the risk. Conventional wisdom is that the Russell 2000 has slightly better returns than the S&P 500, but is slightly more volatile and thus slightly more risky.

My strategy has been to avoid trying to strike it rich, and get steady, decent returns year in and year out.
 
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  • #11
Greg Bernhardt said:
Looking at my positions with the stocks I own I don't see this as the case. Perhaps I should just go into the Vanguard 500 where I'll be given 6-8% on average and then see compounding.
I get the feeling you could benefit from reading more about low-cost diversified index funds. Vanguard offers quite a lot of literature on this if you look on their website. I've been invested with them for many, many years, but there are now quite a few other funds of this type, including so-called ETFs (exchange-traded funds).

When planning a long term portfolio, the most important thing is to set your proportions of asset classes correctly for your investment timeframe. E.g., if you're only invested in stocks (whether US-based or international), that's still really just 1 asset class. The main other asset class is bonds. (Maybe property as well, but that's far less liquid, hence hard to trade unless you use a listed property investment fund, but those tend to behave more like shares than property.) I.e., focus on broad asset classes, not individual stocks/bonds.

For examples of this, take a look at Vanguard's diversified funds -- not just their stocks-only, or bonds-only funds. For a long term (retirement-like) strategy, and minimum rule-of-thumb is to take your age, and have no more than that (as a percentage) in income assets (with the rest in income assets, i.e., bonds). So a young person should be in a high-growth fund, whereas an old person should be more weighted towards income assets.

Btw, Vanguard's diversified funds invest in major markets all over the world, so that gives an extra degree of diversification. They use "passive investing" -- meaning that when one asset class starts to become valued higher than its target percentage range in the fund, they sell some of those assets and buy other lower-valued asset classes. Hence they achieve an automatic mechanism of sell-high/buy-low just by rebalancing their portfolio asset class proportions. A similar thing can be done using the ordinary cash flow through the fund. The beauty of this is that you don't need to rely on expert stocking picking.
 
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  • #12
Investopedia has a good article on comparing ETFs. One should looks at fees.
http://www.investopedia.com/article...-vs-russell-2000-etf-which-should-you-get.asp
http://www.investopedia.com/articles/investing/040516/10-cheapest-vanguard-etfs-voo-vti.asp

On individual stocks, one should look at P/E and EPS, as well as the overall market and sectors, i.e., do one's homework.

One can look at dividends and/or appreciation potential. With good dividends of a few percent or more, once can do dividend reinvestment.
 
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  • #14
@Vanadium 50,

Excellent comments. Most of the staff in Finance Departments that I have worked in could not have explained things so well!
 
  • #15
Greg Bernhardt said:
This thread was spawned off
https://www.physicsforums.com/threads/financial-knowledge-all-adults-should-know.916758/

Do not act on any financial advice here before doing due diligence and meeting with a qualified financial advisor.hmmm I guess I am missing something. If I buy 1 share for $10 and if over a few years it goes up by 10% then I have $11. Where is the compounding?

Hey, Greg

Are you proposing a thread for any and all things investing related in the OP? Or, is this thread devoted to some very specific questions/issues (raised in my other thread)?

I'd love to have a one-stop-shop type of thread for all investing chat. It'd be fun and education, as I'm just getting started and learning. Count me in if it's an investing mega-thread! :smile:
 
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  • #16
Strangerep mentions diversification. He's right, but I think that opens up an even more fundamental question: "When do you need the money?"

If I needed the money next year, I sure wouldn't put it in stocks. Sure, the average return is maybe 10%, but there are some horrible negative outliers. A 1 year treasury would get me 1.22%. I can probably find a 1.25% CD- whether that's better or worse depends on your state's income tax. I'd definitely go for that over buying a mutual fund, and especially over buying a single stock.

This in turn brings up the concept of risk. At it's core, investing is about maximizing return for a given amount of risk (or equivalently, minimizing risk for a given return). If I need a $10,000 a year from now, investing $9900 in a CD today has less risk than investing $9000 in Amazon today. As an investor, it's my job to decide if the reduced risk is worth the $900. This is where diversification comes in - it's a key tool in adjusting risk.
 
  • #17
kyphysics said:
I'd invest in low cost index funds if I had the money.
Greg Bernhardt said:
But how do those generate compound interest?
Reinvested dividends. The Vanguard Total Stock Market Index fund currently yields about 1.8% in dividends. Vanguard Total Bond Market currently yields about 2.3%. With a stock fund you also have capital appreciation (increase in share price), which of course varies a lot and is negative in some years.
 
  • #18
Greg Bernhardt said:
Perhaps there are some stocks with nice dividends, but even then you need a lot of shares to make it worth it.
Dividends are not "free money." A company's profits can be either distributed to shareholders as dividends, or reinvested in the company, which tends to increase the stock price, or held as cash reserves, which also tends to increase the stock price. For investors, this produces a tradeoff between dividends and capital gains. This isn't easy to see with individual stocks because of the normal random variation in stock prices. However, if you compare an index fund that "specializes" in high-dividend stocks with a total market index fund:

vtsmx-vhdyx.gif


This is a "growth chart" that starts with $10K of each fund, and assumes dividends are reinvested.

The dark blue line is Vanguard Total Stock Market Index (VTSMX), which currently yields about 1.8% in dividends. The yellow line is Vanguard High Dividend Yield Index (VHDYX) which currently yields about 3.0% in dividends. How much difference do you see? And when they are noticeably different, which one comes out on top?
 
  • #19
kyphysics said:
Are you proposing a thread for any and all things investing related in the OP? Or, is this thread devoted to some very specific questions/issues (raised in my other thread)?

I'd love to have a one-stop-shop type of thread for all investing chat.
Any type of specific investing questions or commentary, not just general financial advice as the other thread is about.
 
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  • #20
jtbell said:
Reinvested dividends. The Vanguard Total Stock Market Index fund currently yields about 1.8% in dividends. Vanguard Total Bond Market currently yields about 2.3%. With a stock fund you also have capital appreciation (increase in share price), which of course varies a lot and is negative in some years.

Is that technically compounding, though?

Also, you're right that you can lose money too! Although, index funds or slow growth funds/stocks are "safe."

Here's a question:

Assuming your non-stock market financial situation is solid (you have a decent stable income, low to zero debt, no crazy liabilities, etc.), is there any reason to not reinvest dividends in a good fund/stock?
 
  • #21
kyphysics said:
is there any reason to not reinvest dividends in a good fund/stock?

Keeping track of them for tax purposes, but that doesn't apply to 401ks, IRAs, etc.
 
  • #22
I'd recommend looking into buying into some cryptocurrency like ether or bitcoin. Even though they are very volatile many believe there is huge room for growth. I personally believe the etherium protocol is great and I think it will grow.
 
  • #23
kyphysics said:
is there any reason to not reinvest dividends in a good fund/stock?
Imager said:
Keeping track of them for tax purposes, but that doesn't apply to 401ks, IRAs, etc.
Yep, if you automatically reinvest dividends in a taxable account (i.e. not a 401K, IRA, etc.), it's tedious keeping track of the "cost basis" for when you eventually sell. (You pay income tax only on the gains, not on the total proceeds of a sale of stocks or mutual funds.) If you're purchasing new shares regularly anyway, you can take the dividends as cash and add the cash to your regular purchases so as not to create extra "tax lots" of shares.

However, I think for most people who are accumulating money for retirement, that money should go first into tax-deferred accounts. When you sell, you pay tax on the whole proceeds, so cost basis isn't an issue. (The tradeoff is that you don't pay tax on the money that you put into those accounts.) You can contribute up to $5500 per year to IRAs, plus up to $18000 per year in a 401k or 403b if you have one available at work. Most people have to make a lot of money before they can "max out" both contributions and have leftover money for a taxable investment account.
 
  • #24
jtbell said:
Yep, if you automatically reinvest dividends in a taxable account (i.e. not a 401K, IRA, etc.), it's tedious keeping track of the "cost basis" for when you eventually sell. (You pay income tax only on the gains, not on the total proceeds of a sale of stocks or mutual funds.) If you're purchasing new shares regularly anyway, you can take the dividends as cash and add the cash to your regular purchases so as not to create extra "tax lots" of shares.

However, I think for most people who are accumulating money for retirement, that money should go first into tax-deferred accounts. When you sell, you pay tax on the whole proceeds, so cost basis isn't an issue. (The tradeoff is that you don't pay tax on the money that you put into those accounts.) You can contribute up to $5500 per year to IRAs, plus up to $18000 per year in a 401k or 403b if you have one available at work. Most people have to make a lot of money before they can "max out" both contributions and have leftover money for a taxable investment account.

Would the stock/fund holder have to do that or would an accountant (well-paid) do that work (just plop down all your statements on their desk and say, "have fun")? :-p
 
  • #25
guigabyte said:
I'd recommend looking into buying into some cryptocurrency like ether or bitcoin. Even though they are very volatile many believe there is huge room for growth. I personally believe the etherium protocol is great and I think it will grow.

This is gambling, not investing.
 
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  • #26
kyphysics said:
Would the stock/fund holder have to do that or would an accountant (well-paid) do that work (just plop down all your statements on their desk and say, "have fun")? :-p
Actually, your mutual-fund company (if you invest in their funds directly with them) or your brokerage (for stocks and ETFs) has to keep track of cost basis for you. This is a fairly recent thing, since about 2010 or so. At least for mutual-fund companies, not sure about brokerages. Every year they send you a form 1099-B that reports the details of the gains on your sales, for your tax returns. TurboTax and other tax software can import these online so you don't have to type in the numbers yourself. I still like to do it by hand with a spreadsheet, to check their figures and because I feel more comfortable when I understand what's going on.

However, all my ongoing monthly contributions have been to my tax-deferred 403b plan at work, where this doesn't come into play.

I set up my taxable brokerage account with inherited money, and make trades in it only to rebalance, once a year or so. I don't reinvest dividends in that account. I'm retired now, so I collect them and use them to support part of my spending. If I do start reinvesting dividends there at some point, I'll let them accumulate and reinvest them at rebalalancing time. I keep things simple there: Vanguard Total Stock Market Index ETF (VTI), Vanguard Total International Stock Index ETF (VXUS) and Vanguard Total Bond Market Index ETF (BND).
 
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  • #27
My opinion, a beginning investor should write down why they made each purchase. When you sell or ever year, look at the why’s. Use this as tool, to judge if your “whys” are good or bad, or at least if you’re investing on feeling or thinking.

Before investing, you should build up 3 to 9 months of your salary in your savings. It isn’t good when the market drops 20 to 40 percent, and then you lose your job. All too often market drops and layoffs go hand in hand.
 
  • #28
Imager said:
Before investing, you should build up 3 to 9 months of your salary in your savings. It isn’t good when the market drops 20 to 40 percent, and then you lose your job. All too often market drops and layoffs go hand in hand.

For most people, getting started is the problem. Most people struggle to build even a modest amount of savings - to accumulate 3 to 9 months of salary in an account earning next to no interest would take many years. A more realistic approach is to pick a sum you can afford to spend on a regular basis say $10 - $100 p/w and use this for a regular investment into a managed or tracking fund over a 'fixed' period - pick a target of say 10 or 15 years. Small regular payments are quickly absorbed into your budgeting and go unnoticed. Having this money in a fund rather than a savings account makes it harder (but not impossible) to withdraw an will leave you with a good lump sum at the end of your chosen period.
 
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  • #29
Sorry for late reply...
Greg Bernhardt said:
Amazon and Google are obviously giants, but they now have extremely steep prices.
If you mean share price, don't look at it in isolation -- it's an arbitrary number that some companies choose to keep bite sized and some don't. The P/E ratio is pretty high on Amazon though (181).
Would they still be a buy if you are looking at holding them for 20-30 years? Or is it better to play completely safe and throw everything into Vanguard 500? So hold tech giants for 30 years or Van500?
Depends on your risk tolerance. Tech stocks are probably still subject to bubbles more than the market as a whole, but some of the now more established companies look to be juggernauts for a while, but it is really tough to project where tech is going to be in 30 years.

I do own a little bit of Amazon and Facebook, but the vast majority of my money is in S&P500 index funds.
 
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  • #30
guigabyte said:
I'd recommend looking into buying into some cryptocurrency like ether or bitcoin. Even though they are very volatile many believe there is huge room for growth. I personally believe the etherium protocol is great and I think it will grow.
Currency is supposed to be stable to be useful, so there's a self-contradiction in it that makes it seem unlikely to me to be a good idea to consider it an "investment". Also, given its nature and history, I believe it to be highly subject to fraud and possibly even subject to being shut-down by governments.
 
  • #31
Imager said:
Before investing, you should build up 3 to 9 months of your salary in your savings. It isn’t good when the market drops 20 to 40 percent, and then you lose your job. All too often market drops and layoffs go hand in hand.
This is a tough one for me. I find I get antsy to have so much cash not working for me. And I'm not sure if the math really works. Having, say, $50,000 in a savings account costs you $2500 the first year, $2650 the second, $2755 the third, etc. In 8 years, the growth will be more than that 40% potential loss.

I prefer to use my home equity has my major emergency cushion...though I admit I'm not sure how easy it would be to take out a loan if I lose my job...
 
  • #32
Russ, lets' address your second point first. An alternative to a home equity loan is a HELOC - a home equity line of credit. Like a home equity loan it is a second mortgage, but unlike one it has (typically) a ten year "draw period" where you can withdraw money from your line of credit rather than get one lump sum all at once. That way, you pay money only as you need it. One advantage in your situation is that you are approved for such a loan pre-emergency

Now, onto your first point. Cash is part of an asset allocation program. It is working for you. It's reducing risk. Cash and cash-like assets are anticorrelated with the S&P500, so in bear markets, cash tends to do better. You can also use this to your advantage - having cash on hand during a bear market allows you to buy (or avoid selling) when the market is down. As they say, fortunes are made during recessions..
 
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  • #33
The 3 to 9 months is guideline, personally I ran much lower savings when I was younger. In my 50's I had about months 15, then boom the company offers a severance program and I retired.
 
  • #34
Charles Kottler said:
to accumulate 3 to 9 months of salary in an account earning next to no interest would take many years.

I certainly go along with investing a little versus not building a safety fund. I do think people should have some savings to cover unexpected expenses. You should at least be able to fix a transmission or replace an A/C unit without having to sell stocks.
 
  • #35
russ_watters said:
I prefer to use my home equity has my major emergency cushion...though I admit I'm not sure how easy it would be to take out a loan if I lose my job
Many banks are offering 'offset' accounts these days. As the name suggests these offset your current and/or savings account balances against your mortgage. The interest is calculated on the net balance, so if you owe $250,000 on the house and have $50,000 in savings, your mortgage interest is only paid on $200,000 (and you earn nothing from the savings). This allows you to effectively save at your mortgage rate which is typically much higher than the savings rate. While this does not offer quite the same growth potential as shares it is far better than most savings accounts and does still allow you immediate access to the funds.
 
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