Guides

Short answers to questions that come up a lot, backed by the same data and methods the tool uses. Each one links back into Portfolio Lab so you can check the numbers on your own holdings.

• VTI vs VOO: do they overlap?
  VOO is ~85% of VTI. Holding both is one bet split across two tickers.
• Is my portfolio too US-heavy?
  The US is ~60% of global stocks; most US investors hold far more. What a reasonable ex-US weight looks like.
• Did I beat the market, or did I just get lucky?
  Survivorship and start-date luck make almost any record look good. How to actually check.
• How much should I have in bonds?
  The rules of thumb, and what they're really estimating: how large a drop you can hold through.
• How many funds should I own?
  Portfolio Lab's own asset-class map collapses 137 common tickers into 15 real buckets. Most portfolios need 3-6 funds, not more.
• Expense ratio impact over 30 years
  A 1% fee looks small on the label. Compounded monthly for 30 years against the same $10,000, it costs roughly a quarter of the ending balance.
• How often should I rebalance my portfolio?
  Portfolio Lab's own tests show annual and never-rebalanced differ by under 2 points of CAGR on a 60/40 mix — frequency matters less than most people assume.
• Three-fund portfolio vs. target-date fund
  Mechanically almost the same portfolio. The real difference is a ~0.04%/yr DIY cost versus paying a target-date fund to manage the glide path for you.