Stock portfolio value & profit in foreign currency
I think this will do the trick: It's very simple.  Use USDSGD.  Here's why: Presenting profits/losses in other currencies or denominations can be useful if you want to sketch out the profit/loss you made due to foreign currency exposure but depending on the audience of your app this may sometimes confuse people (like yourself).
How can I calculate my currency risk exposure?  You own securities that are priced in dollars, so your currency risk is the amount (all else being equal) that your portfolio drops if the dollar depreciates relative to the Euro between now and the time that you plan to cash out your investments. Not all stocks, though, have a high correlation relative to the dollar.  Many US companies (e.g. Apple) do a lot of business in foreign countries and do not necessarily move in line with the Dollar.  Calculate the correlation (using Excel or other statistical programs) between the returns of your portfolio and the change in FX rate between the Dollar and Euro to see how well your portfolio correlated with that FX rate.  That would tell you how much risk you need to mitigate. how can I hedge against it?  There are various Currency ETFs that will track the USD/EUR exchange rate, so one option could be to buy some of those to offset your currency risk calculated above.  Note that ETFs do have fees associated with them, although they should be fairly small (one I looked at had a 0.4% fee, which isn't terrible but isn't nothing). Also note that there are ETFs that employ currency risk mitigation internally - including one on the Nasdaq 100 .   Note that this is NOT a recommendation for this ETF - just letting you know about alternative products that MIGHT meet your needs. Yes, it's possible and even common but it depends on your bank or broker. One of the main differences is that you might assume FX risk if your account is in EUR and you trade stock denominated in USD. You might also encounter lower liquidity or price differences if you don't trade on the primary exchange where stocks are listed, i.e. NYSE, Nasdaq... International means from all over the world. In the U.S. A Foreign Equity fund would be non-US stocks.  There's an odd third choice I'm aware of, a fund of US companies that derive their sales from overseas, primarily. Foreign stocks tend to be more volatile -- higher risk trades off against higher return potential, always. The better reason for having some money in that area is that, as with bonds, it moves out-of-sync with the US markets and once you pick your preferred distribution, maintaining that balance semi-automatically takes advantage of that to improve your return-vs-risk position. I have a few percent of my total investments in an international stock index fund, and a few percent in an international REIT, both being fairly low-fee. (Low fees mean more of the money reaches you, and seems to be one of the better reasons for preferring one fund over another following the same segment of the market.) They're there because the model my investment advisor uses -- and validated with monte-carlo simulation of my specific mix -- shows that keeping them in the mix at this low level is likely to result in a better long-term outcome than if i left them out. No guarantees, but probabilities lean toward this specfic mix doing what i need. I don't pretend to be able to justify that via theory or to explain why these specific ratios work... but I understand enough about the process to trust that they are on (perhaps of many) reasonable solutions to get the best odds given my specific risk tolerance, timeline, and distaste for actively managing my money more than a few times a year. If that. Foreign stocks have two extra sources of risk attached to them; exchange rate and political.  Exchange rate risk is obvious; if I buy a stock in a foreign currency and there is a currency movement that makes that investment worth less I lose money no matter what the stock does. This can be offset using exchange rate swaps. (This is ceteris paribus, of course; changes in exchange rate can give a comparative advantage to international and exporting companies that will improve the fundamentals and so increase the price of the stock relative to a local firm. The economics of the firms in particular are not explored in this answer as it would get too complicated and long if I did.) Political risk relates not only to the problems surrounding international politics such as a country deciding that foreign nationals may no longer own shares in their national industries or deciding to seize foreign nationals' assets as happens in some areas. Your home country may also decide to apply sanctions to the country in which you are invested thus making it impossible to get your money back even though the foreign country will allow you to redeem them or sell. Diplomatic relations and trade agreements tend to be difficult. There are further problems in lack of understanding of foreign countries' laws, tax code, customs etc. relating to investments and the necessity to find legal representation in a country you may never have visited if there are issues. There is also a hidden risk in that, as an individual investor, you are not likely to be reading the local financial news for that country regularly enough to spot company specific issues arising. By the time these issues get into international media its far too late as all of the local investors have sold out of their positions already. The risks are probably no different if you have the time to monitor international relations and the foreign country's news, and have FX swaps in place to counteract FX risk as the funds and investment banks do but as an individual investor the time required is not feasible. Cross-listing shouldn't be an issue, as the sole reason stocks would behave differently on different exchanges would be due to exchange rates (sure, noise and time differences, but weekly data should take care most of that). If you're using MSCI World index figures in USD, you either have to convert stocks denominated in other currencies to USD at their historical fx rates, or just save a lot of time and use data from stocks listed in the US, when available. If you make money in currency speculation (as in your example), that is a capital gain. A more complicated example is if you were to buy and then sell stocks on the mexican stock exchange.  Your capital gain (or loss) would be the difference in value in US dollars of your stocks accounting for varying exchange rates.  It's possible for the stocks to go down and for you to still have a capital gain, and vice versa. I use Yahoo Finance to plot my portfolio value over time. Yahoo Finance uses SigFig to link accounts (I've linked to Fidelity), which then allows you to see you exact portfolio and see a plot of its historical value. I'm not sure what other websites SigFig will allow you to sync with, but it is worth a try. Here is what the plot I have looks like, although this is slightly out of date, but still gives you an idea of what to expect. "Rebalancing a portfolio helps you reduce risk, sell high, and buy low. I'll use international stocks and large cap US stocks.  They both have ups and downs, and they don't always track with each other (international might be up while large cap US stocks are down and vice-versa) If you started with 50% international and 50% large cap stocks and 1 year later you have 75% international and 25% large cap stocks that means that international stocks are doing (relatively) well to large cap stocks.    Comparing only those two categories, large cap stocks are ""on sale"" relative to international stocks.   Now move so you have 50% in each category and you've realized some of the gains from your international investment (sell high) and added to your large cap stocks (buy low). The reason to rebalance is to lower risk.   You are spreading your investments across multiple categories to manage risk.   If you don't rebalance, you could end up with 95% in one category and 5% in another which means 95% of your portfolio is tied to the performance of a single asset category. I try to rebalance every 12 months and usually get it done by every 18 months.  I like being a hands-off long term investor and this has proven often enough to beat the S&P500." There's no unique way to split the profit, it's about claims and arguments.  I propose the approach based on internal rate of return. Consider we have a project with cash flow -500 at the beginning, -1000 at 3 months and +2300 (1000 profit - 200 fee + 1500 of initial investments) at 1 year. The balance looks as follows (simple compounding): The solution is r = 64% (not bad!). Now, the value of the 1-st investment is 500*(1+0.64)=820 and the value of the second is 1000*(1+0.64*0.75)=1480 (at t=1 year). This gives the shares of 35.65% (820/2300) and 64.35% (1480/2300). Then split the profit according to the shares. "For the S&P and many other indices (but not the DJIA) the index ""price"" is just a unitless number that is the result of a complicated formula.  It's not a dollar value.  So when you divide said number by the earnings/share of the sector, you're again getting just a unitless number that is incomparable to standard P-E ratios. In fact, now that I think about, it kinda makes sense that each sector would have a similar value for the number that you're computing, since each sector's index formula is presumably written to make all the index ""price""s look similar to consumers." "Yes, you're still exposed to currency risk when you purchase the stock on company B's exchange. I'm assuming you're buying the shares on B's stock exchange through an ADR, GDR, or similar instrument. The risk occurs as a result of the process through which the ADR is created. In its simplest form, the process works like this: I'll illustrate this with an example. I've separated the conversion rate into the exchange rate and a generic ""ADR conversion rate"" which includes all other factors the bank takes into account when deciding how many ADR shares to sell. The fact that the units line up is a nice check to make sure the calculation is logically correct. My example starts with these assumptions: I made up the generic ADR conversion rate; it will remain constant throughout this example. This is the simplified version of the calculation of the ADR share price from the European share price:  Let's assume that the euro appreciates against the US dollar, and is now worth 1.4 USD (this is a major appreciation, but it makes a good example):  The currency appreciation alone raised the share price of the ADR, even though the price of the share on the European exchange was unchanged. Now let's look at what happens if the euro appreciates further to 1.5 USD/EUR, but the company's share price on the European exchange falls:  Even though the euro appreciated, the decline in the share price on the European exchange offset the currency risk in this case, leaving the ADR's share price on the US exchange unchanged. Finally, what happens if the euro experiences a major depreciation and the company's share price decreases significantly in the European market? This is a realistic situation that has occurred several times during the European sovereign debt crisis.   Assuming this occurred immediately after the first example, European shareholders in the company experienced a (43.50 - 50) / 50 = -13% return, but American holders of the ADR experienced a (15.95 - 21.5093) / 21.5093 = -25.9% return. The currency shock was the primary cause of this magnified loss.  Another point to keep in mind is that the foreign company itself may be exposed to currency risk if it conducts a lot of business in market with different currencies. Ideally the company has hedged against this, but if you invest in a foreign company through an ADR (or a GDR or another similar instrument), you may take on whatever risk the company hasn't hedged in addition to the currency risk that's present in the ADR/GDR conversion process. Here are a few articles that discuss currency risk specifically in the context of ADR's: (1), (2). Nestle, a Swiss company that is traded on US exchanges through an ADR, even addresses this issue in their FAQ for investors. There are other risks associated with instruments like ADR's and cross-listed companies, but normally arbitrageurs will remove these discontinuities quickly. Especially for cross-listed companies, this should keep the prices of highly liquid securities relatively synchronized." The idea of an index is that it is representative of the market (or a specific market segment) as a whole, so it will move as the market does. Thus, past performance is not really relevant, unless you want to bank on relative differences between different countries' economies. But that's not the point. By far the most important aspect when choosing index funds is the ongoing cost, usually expressed as Total Expense Ratio (TER), which tells you how much of your investment will be eaten up by trading fees and to pay the funds' operating costs (and profits). This is where index funds beat traditional actively managed funds - it should be below 0.5% The next question is how buying and selling the funds works and what costs it incurs. Do you have to open a dedicated account or can you use a brokerage account at your bank? Is there an account management fee? Do you have to buy the funds at a markup (can you get a discount on it)? Are there flat trading fees? Is there a minimum investment? What lot sizes are possible? Can you set up a monthly payment plan? Can you automatically reinvest dividends/coupons?  Then of course you have to decide which index, i.e. which market you want to buy into. My answer in the other question apparently didn't make it clear, but I was talking only about stock indices. You should generally stick to broad, established indices like the MSCI World, S&P 500, Euro Stoxx, or in Australia the All Ordinaries. Among those, it makes some sense to just choose your home country's main index, because that eliminates currency risk and is also often cheaper. Alternatively, you might want to use the opportunity to diversify internationally so that if your country's economy tanks, you won't lose your job and see your investment take a dive. Finally, you should of course choose a well-established, reputable issuer. But this isn't really a business for startups (neither shady nor disruptively consumer-friendly) anyway. Do developing country equities have a higher return and/or lower risk   than emerging market equities?  Generally in finance you get payed more for taking risk.  Riskier stocks over the long run return more than less risky bonds, for instance.  Developing market equity is expected to give less return over the long run as it is generally less risky than emerging market equity.  One way to see that is the amount you pay for one rupee/lira/dollar/euro worth of company earnings is fewer rupees/lira and more dollars/euros. when measured in the emerging market's currency?  This makes this question interesting.  Risky emerging currencies like the rupee tend to devalue over time against less risky currencies euro/dollars/yen like where most international investment ends up, but the results are rather wild.  Think how badly Brazil has done recently and how relatively well the rupee has been doing.   This adds to the returns (roughly based on interest rates) of foreign stocks from the point of view of a emerging market investor on average but has really wild variations. Do you have data for this over a long timeframe (decades), ideally for multiple countries? Not really, unfortunately.  Good data for emerging markets is a fairly new phenomenon and even where it does exist decades ago it would have been very hard to invest like we can now so it likely is not comparable. Does foreign equity pay more or less when measured in rupees (or other   emerging market currency)? Probably less on average (theoretically and empirically) all things included though the evidence is not strong, but there is a massive amount of risk in a portfolio that is 85% in a single emerging market currency.  Think about if you were a Brazilian and needed to retire now and 85% of your portfolio was in the Real.  International goods like gas would be really expensive and your local currency portfolio would seem paltry right now.  If you want to bet on emerging markets in the long run I would suggest that you at least spread the risk over many emerging markets and add a good chunk developed to the mix. As for investing goals, it's just to maximize my return in INR, or maximize my risk-adjusted return. That is up to you, but the goal I generally recommend is making sure you are comfortable in retirement.  This usually involves looking for returns are high in the long run, but not having a ton of risk in a single currency or a single market.  There are reasons to believe a little bias toward your homeland is good as fees tend to be lower on local investments and local investments tend to track closer to your retirement costs, but too much can be very dangerous even for countries with stronger currencies, say Greece. The US doesn't have a Value Added Tax, which is the one usually refundable upon departing the country... so sales taxes you pay in this country stay in this country and you don't get a refund. Just remember to treat the tax as an implied part of the price. (And be aware that state and local taxes may vary, so the total price may be higher in one place than in another. New York City adds a few percent on top of the state sales tax, for example.) If you aren't sure how much tax would be, don't be afraid to ask.