<prompt> Human: The 30-year average for the SP is a 12 return. Everything a Ive read suggests that we should not expect that high of a return in the future, with varying suggestions about what one should expect. Ive heard 7 is what we should use to plan, with some suggesting 6 or even 5,1. For the purposes of planning, what percentage do you use?2. Is there even a theoretical future where returns stay strong in the 10 space?  <response>: I use 5 too, but that is not my estimate for the SP. Its for my portfolio in total, which includes bonds, other equity indexes, REITs, and my individual mistakes and successes. I think 5 is conservative enough to ensure that I save enough to hit my goal. 