Probably this is the best calculator to use. This one is total return with dividend included and inflation adjusted. https://dqydj.com/nikkei-return-calculator-dividend-reinvestment/
Well I have used this calculators long ago. That's why I always question people when they bring up "terrible" Nikkei's return. Nikkei is actually go up more than S&P when both are denominated with yen or dollar.
Getting back to the main point about the thread, even with that spectacular return of Nikkei over 40 years investor couldn't survive less than 2% safe withdrawal rate over 30 years. That is the power of diversification. Same investor with few international stocks and bonds along with their own country bonds would have fared much better. Anyway yesterday's article from RA probably relevant to this thread http://bit.ly/2zduV5B
Ray Dalio has some gold as a diversifier/insurance even though he sees bets with higher expected value. Protecting large amounts of money against tails is important to some rational people. Buffett, who I greatly admire as an investor/speculator and as a person, handles things differently and does not own gold. However, Buffett thinks a lot about risk and tail risk.