For bonds, I did the age minus ten. I was actually thinking of increasing my international proportion, to better emulate the proportion of US/Intl by market-cap. What are your thoughts? What resources would you recommend to get better informed?
The age minus 10 is a modification of the original rule of using your age as the basis for bond holdings. As time went on and people started living longer, the rules were modified. You're using age minus 10. Current thinking for a lot of folks now is age minus 20 (or 120 minus your age to arrive at the equity percentage).
Frankly, rules of thumb are just that -- a guideline (not a hard and fast rule) for where you should be and for most people, they're about right. It's important to understand these guidelines because you know the reasoning that goes into them, so you'll know if your particular circumstances should deviate from it. Also, your individual risk tolerance plays a part in all this. You want to take on enough risk so that your money grows fast enough so you don't want to outlive your money. But at the same time, it's no good to take on a ton of risk if you wind up staying awake at night worrying about how much money you've lost during a market downturn. That's why I prefer guidelines that incorporate a range rather than a straight calculation.
Now let's get to your particular case. If you refer to page 12 of the Transparent Investing document you read a year and a half ago, you'll see a table called Common Portfolio Guidelines. As you can see for holdings of 20+ years, you fall within the recommended range but pretty far over on the conservative side. There's nothing wrong with that but as I say, I think you can afford quite a bit more risk. You've got over a quarter century left to go, but you're edging close to the (risky side of the) recommended ratio for an investment period of 10 years. Personally, I lean toward higher risk, but I'm unusually risk tolerant. You might be fine just where you are. That's up to you to decide.
As for the International vs. US allocation, you can see in http://www.cbsnews.com/news/asset-allocation-guide-us-vs-international-equity/
that he recommends 30-50% International allocation for equities. Your allocation pretty much places you squarely in the middle of that range, which is fine. But what do other experts do? I took a look at what the target retirement funds for 2040 look like and here's where they stand:
- Vanguard 2040 - US Stocks 63.2%, International Stocks 26.8%, Bonds 10%
- T Rowe Price 2040 - US Stocks 58.4%, International Stocks 30%, Bonds and Other 11.6%
- Fidelity 2040 - US Stocks 63.1%, International Stocks 27%, Bonds and Other 9.8%
What does the above tell you? All of them hover around 90% in equities and within the equity portion, the international allocation is around 30% vs. the 40% you have in your portfolio. Are they right? Are you wrong? Nobody knows. Don't make yourself crazy second-guessing yourself. All I'm saying in my previous post is that your allocation seems a bit conservative (by holding a lot of bonds) and a little heavier in International stocks than most portfolios given your timeline. But as mentioned above, you're certainly within the range that most people would recommend. If you're happy with your current allocation, don't change it. If you'd like a bit more money when you retire (assuming this is at 67 years old), then pull back on the bonds a bit, at least for now. If you're leery of doing this as the US Markets hit all time highs, just DCA your money into stocks over time.