Why buy bonds in a no-arbitrage market?
Rates are a complex field. I will assume that context wise you are talking about rates for a individual saver quantities. The two rates you are asking about are personal bank saving account and exchange traded bonds. The points you want to compare between them are. In general, a bond is what we called a fixed rate instrument. This means that for the life of the product, it will yield a fixed percentage of its face value at a regular period. Baring any extreme circumstances (such as bankruptcy), no external factors will change the payment schedule on a bond. Conversely, by placing your money into a bank, you will accrue interest rate at some value related to some published interest rate. For example, if tomorrow, the Treasury decided to try to stimulate the economy, they could slash the interest rate, this would directly affect the rate at which your savings account would accrue interest. In general, a bond has a maturity date, where the capital is finally released from the bond. Until such date, you cannot access the money directly (you can however sell the bond, but it would likely be at a discounted value). Therefore, in general, you cannot get access to the money whenever you want it. As for a saving account, normally one can access the funds instantly, if not within a few days. This seems to the reason people seem to be focusing on. For each bond, the issuer of the bond is obligated to pay you the holder of the bond fixed payments at an interval, plus the capital at the maturity. However, obligation does not mean guarantee. If the issuer, is unable to make the payments, they may go into bankruptcy to avoid paying you. There are companies setup to advise people on the likelihood of each bond issuer on their ability to honour their debts. For example Standard and Poor issues a rating which goes all the way up to AAA for bonds. Recently, many sovereign countries have lost their AAA rating from S&P. Meaning that S&P feel that the possibility of these countries going bankrupt is non-zero. Conversely, banks may also be unable to give you your money when requested. In the US, the reserve requirements means that at any one time it only holds 10% of the money it owes to its customers. This can mean that if every customer turns up to the bank to demand their money, that bank would be unable to pay. This situation is called a Bank Run. During such a situation, the bank would likely collapse and default. In many modern countries, the government put into place guarantees on the first xxx amount in saving accounts, but otherwise, your savings could be lost. There are many complex reasons to choose one instrument over another (including some I have avoided), even if at the outset, they could appear to have the same rates. For safety. If something catastrophic happens to your bank and your money is in there you will lose any not covered by FDIC. So if you have a very large amount of money you will store it in bonds as its much less likely that the US treasury will go bankrupt than your bank. I also literally just posted this in another thread: Certain rules and regulations penalize companies or institutions for holding cash, so they are shifting to bonds and bills. Fidelity, for example, is completely converting its $100 billion dollar cash fund to short term bills. Its estimated that over $2 trillion that is now in cash may be converted to bills, and that will obviously put upward preasure on the price of them. The treasury is trying to issue more short term debt to balance out the demand. read more here: http://www.wsj.com/articles/money-funds-clamor-for-short-term-treasurys-1445300813 "If by ""putting money in the bank"" you mean regular savings or checking, then the bond locks a rate for a period of time, whereas your savings/checking rate can vary over that period.  That variation might go for you or against you.  Depending on your situation, you might prefer to take a determined rate to the variations.  In addition, some bond types provide tax benefits (e.g. treasuries and municipal bonds) that change the effective return - You cannot just compare the interest rates. Finally, the bonds have ""resale"" value on the secondary market like stock - Depending on your outlook and strategy, you might by the bond for its value as a security rather than for the interest specifically just like you'd could buy a dividend-paying stock for its value as a security rather than for the dividend.  In other words, you might think that bond values are going up, so you buy bonds with the intent of making a capital gain rather than counting on the interest returned. (The bond market does depend on the interest rate, so these are not independent factors.) I see the other answer that mentions the potential for your bank busting and you losing money beyond the FDIC insurance limit.  The question doesn't specify U.S. Government bonds though, so I don't think that answer is generally good.  It would be good in the case that you had a lot of money (especially an institution or foreign government) and you were specifically interested in U.S. Treasury bonds.  Not so much if you invest in corporate bonds where you have no government insurance / assurance of any sort.  Municipal bounds are also not backed by the U.S. (federal) government, but they may have some backing at the state level, depending on the state." There is no single 'market interest rate'; there are myriad interest rates that vary by risk profile & term. Corporate bonds are (typically) riskier than bank deposits, and therefore pay a higher effective rate when the market for that bond is in equilibrium than a bank account does. If you are willing to accept a higher risk in order gain a higher return, you might choose bonds over bank deposits. If you want an even higher return and can accept even higher risk, you might turn to stocks over bonds. If you want still higher return and can bear the still higher risk, derivatives may be more appealing than stocks. It is my understanding that banks pay less than the going rate on savings accounts and require that the person who takes out a loan pay more than the going rate. That is how the bank gets its money.  Usually the going rate is affected by the current inflation rate (but that has not been true for the last few weeks). So that means that, typically, the money you have in the bank is, gradually, losing purchasing power as the bank typically pays you less than the inflation rate.  So if you want your money to keep pace with inflation (or do a bit better) then you should buy bonds. Bonds can increase in price, if the demand is high and offer solid yield if the demand is low.  For instance, Russian bond prices a year ago contracted big in price (ie: fell), but were paying 18% and made a solid buy.  Now that the demand has risen, the price is up with the yield for those early investors the same, though newer investors are receiving less yield (about 9ish percent) and paying higher prices.   I've rarely seen banks pay more variable interest than short term treasuries and the same holds true for long term CDs and long term treasuries.  This isn't to say it's impossible, just rare.  Also variable is different than a set term; if you buy a 10 year treasury at 18%, that means you get 18% for 10 years, even if interest rates fall four years later.   Think about the people buying 30 year US treasuries during 1980-1985.  Yowza. So if you have a very large amount of money you will store it in bonds as its much less likely that the US treasury will go bankrupt than your bank. Less likely?  I don't know about your bank, but my bank doesn't owe $19 trillion.
In theory, in a perfect world, what you state is almost true. Apart from transaction fees, if you assume that the market is perfectly efficient (ie: public information is immediately reflected in a perfect reflection of future share value, in all share prices when the information becomes available), then in theory any transaction you would choose to take is opposed by a reasonable person who is not taking advantage of you, just moving their position around. This would make any and all transactions completely reasonable from a cost-benefit perspective.  ie: if the future value of all dividends to be paid by Apple [ie: the value of holding a share in Apple] exactly matches Apple's share price of $1,000, then buying a share for $1,000 is an even trade. Selling a share for $1,000 is also an even trade. Now in a perfectly efficient market, which we have assumed, then there is no edge to valuing a company using your own methods. If you take Apple's financial statements / press releases / reported information, and if you apply modern financial theory to evaluate the future dividends from Apple, you should get the same $1,000 share price that the market has already arrived at. So in this example, why wouldn't you just throw darts at a printout of the S&P 500 and invest in whatever it lands on? Because, even if the 'perfectly efficient market' agrees on the true value of something, different investments have different characteristics. As an example, consider a simple comparison of corporate bonds: Corporations make bond offerings to the public, allowing individual investors to effectively lend money to the corporation, for a future benefit. For simplicity, assume a bond with a 'face value' (the amount to be repaid to the investor on maturity) of $1,000 has these 3 defining characteristics: (1) The price [What the investor pays to acquire it]; (2) Interest payments [how much, if any, the corporation will pay to the investor before maturity, and when those payments will be made]; and (3) a bond rating [which is a third party assessment of how risky the bond is, based on the 'health' of the corporation]. Now if the bond rating agency is perfect in its risk assessment, and if the price of all bond's is fair, then why does it matter who you loan your money to? It matters because different people want different things out of their investments. If you are waiting to make a down payment on a house next year, then you don't want risk - you want to be certain that you will get your cash back, even if it means lower returns. So, even though a high-risk bond may be perfectly priced, it should only be bought by someone willing to bear that risk. If you are retired, and you need your bonds to pay you interest regularly as your sole source of income, then of course a zero-coupon bond [one that pays no interest] is not helpful to you. If you are young, and have a long time to invest, then you may want risk, because you have time to overcome losses and you want to get the most return possible. In addition, taxes are not universal between all investors. Some people benefit from things that would be tax-heavy to their neighbors. For example in Canada, there is a 'dividend tax credit' which reduces the taxes owing on dividends received by a corporation. This credit exists to prevent 'double-taxation', because otherwise the corporation would pay its ~30% of tax, and then a wealthy investor would pay another ~45% of tax. Due to the mechanics of how the credit is calculated, however, someone who makes less money, gets an even lower tax bill than they normally would. This means that someone making under the top tax bracket in Canada, has a tax benefit by receiving dividends. This means that while 2 stocks may be both fairly priced, if one pays dividends and the other doesn't [ie: if the other company instead reinvests more heavily in future projects, creating even more value for shareholders down the road], then someone in the bottom tax brackets may want the dividend paying stock more than the other. In conclusion: Picking investments yourself does require some knowledge to prevent yourself from making a 'bad buy'; this is because the market is not perfectly efficient. As well, specific market mechanics make some trades more costly than they should be in theory; consider for example transaction fees and tax mechanics. Finally, even if you assume that all of the above is irrelevant as a theoretical idea, different investors still have different needs. Just because $1,000,000 is the 'fair' price for a factory in your home town, doesn't mean you might as well convert your retirement savings to buy it as your sole asset. You're missing the cost-of-carry aspect: The cost of carry or carrying charge is the cost of storing a physical commodity, such as grain or metals, over a period of time. The carrying charge includes insurance, storage and interest on the invested funds as well as other incidental costs. In interest rate futures markets, it refers to the differential between the yield on a cash instrument and the cost of the funds necessary to buy the instrument. So in a nutshell, you'd have to store the gold (safely), invest your money now, i.e. you're missing out on interests the money could have earned until the futures delivery date.  Well and on top of that you need to get the gold shipped to London or wherever the agreed delivery place is. Edit: Forgot to mention that of course there are arbitrageurs that make sure the futures and spot market prices don't diverge. So the idea isn't that bad as I might have made it sound but being in the arbitrage business myself I should disclaim that profits are small and arbitraging is highly automated, so before you spot a $1 profit somewhere between any two contracts, you can be quite sure it's been taken by an arbitrageur already. The literal answer to your question 'what determines the price of an ETF' is 'the market'; it is whatever price a buyer is willing to pay and a seller is willing to accept. But if the market price of an ETF share deviates significantly from its NAV, the per-share market value of the securities in its portfolio, then an Authorized Participant can make an arbitrage profit by a transaction (creation or redemption) that pushes the market price toward NAV. Thus as long as the markets are operating and the APs don't vanish in a puff of smoke we can expect price will track NAV. That reduces your question to: why does NAV = market value of the holdings underlying a bond ETF share decrease when the market interest rate rises?  Let's consider an example. I'll use US Treasuries because they have very active markets, are treated as risk-free (although that can be debated), and excluding special cases like TIPS and strips are almost perfectly fungible. And I use round numbers for convenience. Let's assume the current market interest rate is 2% and 'Spindoctor 10-year Treasury Fund' opens for business with $100m invested (via APs) in 10-year T-notes with 2% coupon at par and 1m shares issued that are worth $100 each. Now assume the interest rate goes up to 3% (this is an example NOT A PREDICTION); no one wants to pay par for a 2% bond when they can get 3% elsewhere, so its value goes down to about 0.9 of par (not exactly due to the way the arithmetic works but close enough) and Spindoctor shares similarly slide to $90. At this price an investor gets slightly over 2% (coupon*face/basis) plus approximately 1% amortized capital gain (slightly less due to time value) per year so it's competitive with a 3% coupon at par.  As you say new bonds are available that pay 3%. But our fund doesn't hold them; we hold old bonds with a face value of $100m but a market value of only $90m. If we sell those bonds now and buy 3% bonds to (try to) replace them, we only get $90m par value of 3% bonds, so now our fund is paying a competitive 3% but NAV is still only $90.  At the other extreme, say we hold the 2% bonds to maturity, paying out only 2% interest but letting our NAV increase as the remaining term (duration) and thus discount of the bonds decreases -- assuming the market interest rate doesn't change again, which for 10 years is probably unrealistic (ignoring 2009-2016!). At the end of 10 years the 2% bonds are redeemed at par and our NAV is back to $100 -- but from the investor's point of view they've forgone $10 in interest they could have received from an alternative investment over those 10 years, which is effectively an additional investment, so the original share price of $90 was correct. "I can, but it takes a significant amount of time.   I'll do a short version which unfortunatley might leave more holes than you like. Basically, traders don't want to barter because it is hard to find the person with precisely the goods you want who wants to trade for the goods you have. Thus the need for ""coupons"" that represent value in a marketplace. Then you need to decide who gets to create coupons. If too many can issue them, problems arise, and no one trusts the coupons will be good later. Eventually you want one large bank/nation/trader to be able to issue them so everyone has the same level of trust in them, and you don't have the economic inefficiencies of many coupon issuers.  Next, the number of coupons needs to be enough to facilitate trade. If the amount of trade increases a lot, and the number of coupons doesn't increase similarly they become worth more, and people start to hoard them. This causes deflation, which causes less investment, which causes less growth, which hurts everyone in the long run.   If there are too many coupons added, this causes inflation, which causes people to spent them quicker instead of holding them. For reasons I won't cover here slight, predictable inflation is much better than deflation, so remember inflation is slightly preferred. Note that inflation is often caused not by the number of coupons but by external price changes.  Now, for a modern economy to do well, somone has to watch the economy, measure it carefully, and add/subtract coupons into the system as needed. Coupons, like all money, have no real value (whatever that means), but only have value because the holder expects to be able to trade them *later* for goods and services. You cannot eat coupons, use them for shelter (usually!), or wear them, but you want to trade them for such needs. The same is true for paper money, gold, stones, or almost whatever money system one uses. Money in all these forms is merely an IOU tradable for future goods.  The Fed is tasked (among other things) with making sure there is precisely enough coupons in the economy to keep trade functioning as well as possible. This is very hard to do since there are external and internal shocks to an economy (think disaster, foreign govts shutting off resources, rapid changes in people's tastes, etc.).   Central banks such as the Fed need to be independent of political control, since empirical evidence has shown that politicians tend to add more money to the system than is needed, because the short term gains give them votes, but the long term consequences (rapid inflation, unemployment, lower economic growth) are bad for society. This is why the Fed is largely out of congressional control, and large amounts of empirical evidence across hundreds of years and dozens of cultures shows this to be good.  Note: another function of the Fed is to be a lender of last resort to help prevent bank panics that were widespread in the 18th and early 19th century, something that none of us now remember, but it was a real problem. I'll skip that part for now.  So now we're at the point where the Fed needs to add/subtract coupons from society. To do this part justice takes significant time to cover all the reasons why various rules are in place (banking reserve requirements, for example), and you cannot learn it from one pass of reading.  But I'll try. Instead of being like the majority of internet fools that rail against the system, try to learn the *why* of all this, and you'll be much wiser and understand that it is all a pretty good system.  One method they use is the interbank lending rate. Banks have a reserve requirement, which is the ratio of coupons they need to have on hand as a ratio compared to the total coupons depositors lent them. This is usually around 1:10. The amount deposited that they can lend goes to business loans, school loans, mortgage loans, etc., and helps economies grow. Now when a bank on a given day falls short due to too many withdrawals, other banks (or the Fed) offers an overnight loan to meet reserve requirements, and the Fed sets the interest rate, which in turn drives other interest rates in the system.  This does not change the money supply very much.  Secondly, the Fed sets the reserve requirement, which vastly can change the amount of money available to society. But they change this rate so rarely (all the historical data is on the St. Loius Fed site, among others) that it is not usually an issue. I'll explain below how this can drastically change the money supply though the money multiplier.  Thirdly, and this is the part the poster above seems upset about, they conduct open market operations. This is the primary means by which the Fed exercises control over the number of coupons in play. The government, like businesses, like individuals, often needs to borrow money, in theory to invest in wise causes like infrastructure or perhaps money making enterprises such as technology investmeny (and I know what they often use the money for causes many to complain). The government, like companies, offers the sale of various contracts such as bonds to investors, who want a place to park some accumulated coupons for safety, and they get a return plus some interest. So the government sells bonds on the open market to investors, banks, pensions, foreign governments, basically to whomever wishes to purchase them at the market rate, and the government, like many individuals and banks, uses these loans to perform day to day functioning and possible smooth out volatility in spending needs. By law the Fed cannot purchase directly from Treasury. Now, once on the market, these bonds are traded, packaged, resold, etc., since they have inherent value, and since those owning them want to buy/sell them, perhaps before maturity date. This ""liquidity"" (ability to sell your goods) is necessary - fewer would purchase an item if they could not sell it when they desire. Thus bonds are bought, sold, and traded, and their prices fluctuate based on what the market thinks they are worth, just like any good.  Now, the Fed can buy/sell these bonds on the *open market*, like anyone else. So when the Fed wishes to increase the money supply, they can buy bonds that are not ""spendable"" money and inject money into the system. Note they now hold a bond that had at the time of transaction the same value as the money they injected. Note investors freely bought these from Treasury, meaning the market thought at the time of purchase that this was a good invesement. It is *not* the government merely wishing more money into existance. It is market forces that require more money for trades and is selling goods from the marketplace of (presumably) equal value to the Fed. This increases liquidity, but takes valuable assets from circulation. When the Fed wishes to shrink the money supply, they sell these bonds back into circulation basically by offering better terms than Treasury. In fact, you can find graphs of the Fed operations and see how every December they inject money for more Christmas shpping (need more coupons for more trade) and every January they extract some.  So open market transactions, buying and selling goods at market prices in the marketplace along with other traders, is how the Fed injects and removes money from the money supply. This is the primary mechanism that the Fed uses to control the number of coupons in the economy.  Finally, a little about reserve requirements and the money multiplier, since it affects so much of the number of coupons in play. This also I must simplify drastically. Each bank needs to hold 1/10 of all deposits in cash. The rest can be lent, which lands in another bank, which again can be lent, etc... Thus each $1 deposited can result in loans totalling 9/10 + (9/10)^2 + (9/10)^3 +... = 9 more dollars. Many people claim that banks are printing money, which is nonsense, since each also has an equal debt to pay to the person they borrowed from. When all loans are paid back there is no net money gain.  However, this allows for each $1 the Fed injects by buying bonds for there to be up to $9 in the economy, *if banks all loan to the fullest extent*. Banks tend to want to loan since loaned money makes them profit. Banks used to loan too much and runs on the banks caused significant problems, which is why laws were made to require *all* banks to have the same reserve requirement.  Now, when banks get scared and stop loaning, this 9 fold multiplier dries up, and the Fed has much less inpact on being able to target the proper number of coupons to keep the economy smooth. During the recent crash when banks stopped loaning, as each dollar was paid back on debts, there was significant shrinkage of available money for transactions, and this kills the economy. This is the ""liquidity crisis"".   Hope this helps. As I said, this is vastly simplified and I cannot go into all the reasons and historical items needed to understand it fully. It is a vastly complex (and necessarily so) and takes significant study to grasp the genius of it. It's similar to not being able to understand nuances of particle physics in one go, but as you study and work at it you see *why* things go as they do, and you learn all the failed methods (the gold standard is one example) that were thrown out for many good reasons.  Cheers." No I get that.  But if you don’t want risk, then buy bonds.  Long term an S&amp;P Index has very low risk.  On the other hand, actively managed funds have fees that take out a ton of the gain that could be had.  I don’t have time to look for the study but I read recently that 97% of actively managed funds were outperformed by S&amp;P Indexes after fees.  Now I don’t know about you but I think the risk of not picking a top 3% fund is probably higher than the safe return of index’s. There are really two answers, depending on your goal. You're either trying to preserve wealth, or increase wealth. In the case of preserving wealth, undervalued blue chip stocks are always a great move. Bonus points if they have a history of increasing dividend payments. The best example I have is bank stocks - the continuously change their dividend payouts (usually to the benefit of investors), and at the same time, many have been undervalued, or over-whelped during the downturn.  Alternatively, you can let things sit, and buy high quality corporate bonds. I'm seeing (daily) offers from my brokerage's new issues list for high quality bonds paying 5.75%-7.25%. While you have to lock in your money for the period, the rate of return tends to offset lock-in worries, and you can still usually sell the shares in a secondary market, or through your broker. In answer to your last formulation, no. In a perfectly efficient market, different investors still have different risk tolerances (or utility functions). They're maximizing expected utility, not expected value.  The portfolios that maximize expected utility for different risk preferences are different, and thus generally have different expected values. (Look up mean-variance utility for a simple-ish example.)  Suppose you have log utility for money, u(x) = log(x), and your choice is to invest all of your money in either the risk-free bond or in the risky bond. In the risky bond, you have a positive probability of losing everything, achieving utility u(0) = -\infty. Your expected utility after purchase of the risky bond is:  Pr(default)*u(default) + (1-Pr(default))*u(nominalValue).  Since u(default)= -\infty, your expected utility is also negative infinity, and you would never make this investment. Instead you would purchase the risk-free bond.  But another person might have linear utility, u(x) = x, and he would be indifferent between the risk-free and risky bonds at the prices you mention above and might therefore purchase some. (In fact you probably would have bid up the price of the risk-free bond, so that the other investor strictly prefers the risky one.) So two different investors' portfolios will have different expected returns, in general, because of their different risk preferences. Risk-averse investors get lower expected value. This should be very intuitive from portfolio theory in general: stocks have higher expected returns, but more variance. Risk-tolerant people can accept more stocks and more variance, risk-averse people purchase less stocks and more bonds. The more general question about risk premia requires an equilibrium price analysis, which requires assumptions about the distribution of risk preferences among other things. Maybe John Cochrane's book would help with that---I don't know anything about financial economics. I would think that in the setup above, if you have positive quantities of these two investor types, the risk-free bond will become more expensive, so that the risky one offers a higher expected return. This is the general thing that happens in portfolio theory. Anyway. I'm not a financial economist or anything.  Here's a standard introduction to expected utility theory: http://web.stanford.edu/~jdlevin/Econ%20202/Uncertainty.pdf If you have two other assets whose payoffs tomorrow are known and whose prices today are known, you can value it.  Let's say you can observe a risk-free bond and a stock. Using those, you can calculate the state prices/risk-neutral probabilities. NOTE: You do not need to know the true probabilities.   The value of your asset is then the state-price weighted sum of future payoffs.