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What low-fee & liquid exchange-traded index funds / ETFs should I consider holding in a retirement portfolio?
Here's a dump from what I use. Some are a bit more expensive than those that you posted. The second column is the expense ratio. The third column is the category I've assigned in my spreadsheet -- it's how I manage my rebalancing among different classes. "US-LC" is large cap, MC is mid cap, SC is small cap. "Intl-Dev" is international stocks from developed economies, "Emer" is emerging economies. These have some overlap. I don't have a specific way to handle this, I just keep an eye on the overall picture. (E.g. I don't overdo it on, say, BRIC + Brazil or SPY + S&P500 Growth.) The main reason for each selection is that they provide exposure to a certain batch of securities that I was looking for. In each type, I was also aiming for cheap and/or liquid like you. If there are substitutes I should be looking at for any of these that are cheaper and/or more liquid, a comment would be great. High Volume: Mid Volume (<1mil shares/day): Low Volume (<50k shares/day): These provide enough variety to cover the target allocation below. That allocation is just for retirement accounts; I don't consider any other savings when I rebalance against this allocation. When it's time to rebalance (i.e. a couple of times a year when I realize that I haven't done it in several months), I update quotes, look at the percentages assigned to each category, and if anything is off the target by more than 1% point I will buy/sell to adjust. (I.e. if US-LC is 23%, I sell enough to get back to 20%, then use the cash to buy more of something else that is under the target. But if US-MC is 7.2% I don't worry about it.) The 1% threshold prevents unnecessary trading costs; sometimes if everything is just over 1% off I'll let it slide. I generally try to stay away from timing, but I do use some of that extra cash when there's a panic (after Jan-Feb '09 I had very little cash in the retirement accounts). I don't have the source for this allocation any more, but it is the result of combining a half dozen or so sample allocations that I saw and tailoring it for my goals.