John Bogle Investment Analysis Prompt
A complete index investing framework based on John Bogle's philosophy. Covering cost analysis, market efficiency, asset allocation, diversification, and behavioral discipline to help you build a simple, low-cost investment portfolio.
Full Prompt Content
Classic Investment Rules
Deep dive into the timeless investment principles that have guided generations of successful investors.
Enough
There is no amount of money that will ever be enough for someone who doesn't know what enough is. Define your enough.
→Don't Peek
Don't peek at your portfolio constantly. The more you look, the more likely you are to make an emotional mistake.
→Bond Allocation Rule
A rough rule: hold your age in bonds. A 30-year-old might hold 30% bonds, a 60-year-old 60% bonds.
→Asset Allocation
Your asset allocation - the mix of stocks, bonds, and cash - is the most important investment decision you'll make.
→Reversion to the Mean
Fund returns tend to revert to the mean. Yesterday's winners become tomorrow's losers, and vice versa.
→Common Misconceptions
What are common misconceptions about index investing?
**Misconception 1: "Index returns are too low"**
- S&P 500 averaged ~10% annually over 50 years, beating 85%+ of active funds
- "Average return" is actually "better than most people's return"
**Misconception 2: "Should sell index funds in bear markets"**
- Market timing almost never works; missing the best few days drastically reduces returns
- Selling in late 2008 meant missing the next 10-year bull run
**Misconception 3: "Index funds need no management"**
- Need annual rebalancing (return to target allocation)
- Adjust stock/bond ratio as you age
- Choosing low-fee products still matters
**Misconception 4: "Chinese market unsuitable for indexing"**
- A-shares volatile, but long-term DCA still yields decent returns
- Broad indexes eliminate worst companies, automatic survival of the fittest
Practical Application
How can ordinary investors apply Bogle's index investing method?
**Step 1: Choose fund**
- Select lowest-fee broad market index fund (CSI 300, S&P 500 ETF)
- Fees below 0.2%/year
- Large scale, good liquidity
**Step 2: Dollar-cost average**
- Buy fixed amount monthly
- No market timing, no chart watching
- Auto-deduct after salary arrives
**Step 3: Hold**
- Hold minimum 10+ years
- Don't sell during crashes (this is the opportunity to buy cheap)
- Don't add during surges (maintain discipline)
- Only action needed: rebalance once annually
**Bogle's quote**: "Don't look for the needle in the haystack. Just buy the haystack"
Comparison & Selection
Does Bogle's passive investing contradict Buffett's active stock picking?
**Buffett himself recommends index funds**:
- Buffett's will advises his wife to put 90% in S&P 500 index fund
- His bet with hedge fund managers (2007-2017): index fund won decisively
- Buffett says: unless you have ability and time for deep research, index funds are best
**Difference is "circle of competence"**:
- Buffett has 60 years experience + top business judgment → active picking advantageous
- Ordinary people don't have these → passive index more suitable
- Bogle's method suits 99% of people; Buffett's suits the top 1%
**Conclusion**: Their advice doesn't contradict — for ordinary people, Bogle is the right answer
Usage Scenarios
When should you use John Bogle's method?
Theory Deep Dive
What is the core of Bogle's index investing theory?
**Law 1: Costs are crucial**
- Fund returns = Market returns - Costs
- Average return of all investors = market return (zero-sum game)
- Therefore low cost = above-average net returns
**Law 2: Most active management underperforms index**
- Over 15 years, 85-90% of active funds trail the index
- Not because managers aren't smart, but fees and trading costs eat the edge
**Law 3: Long-term compounding is remarkable**
- 1% fee difference creates 25%+ asset gap over 30 years
- The longer the period, the larger the low-cost advantage
**Conclusion**: Buy total market index fund, hold still, is the optimal strategy for most people
Basic Usage
What is John Bogle's investment philosophy?
Bogle founded the world's first index fund (Vanguard 500) in 1976, with core principles including:
1. **Cost matters**: High management fees of active funds (averaging 1-2%) severely erode long-term returns. Index funds' low fees (typically <0.2%) allow investors to retain more gains
2. **Market efficiency**: In efficient markets, efforts to pick stocks or time the market are often futile. The best strategy is to **buy and hold the entire market**
3. **Power of compounding**: Seemingly small fee differences, compounded over 30-40 years, lead to enormous wealth gaps
Bogle proved with data: over the past 50 years, less than 15% of active funds could outperform the S&P 500 index long-term. His famous maxim is: "In investing, you get what you don't pay for." Therefore, for the vast majority of investors, **low-cost market index funds are the optimal choice**.
Effectiveness & Accuracy
Can index funds really outperform most active funds long-term?
📊 **Data support**:
- SPIVA report: Over 15 years, 85-90% of active funds underperform S&P 500
- Fee difference: Index fund 0.03-0.1%/year vs active fund 1-2%
- 20-year compounding: 1% annual fee gap can cause 20%+ difference in final assets
✅ **Best suited for**:
- People without time for stock research
- Long-term investors seeking market average returns
- Retirement and long-term funds
⚠️ **Caveats**:
- Doesn't apply to all markets (less efficient emerging markets may favor active management)
- Choose funds with low tracking error and fees
Result Interpretation
Is AI-suggested index fund allocation reliable?
Bogle's core: "no complex analysis needed":
- Buy total market index funds
- Hold long-term, no timing
- Minimize costs
AI suggestions for index funds usually fine, but check:
1. Fee comparison: Are recommended funds lowest cost?
2. Tracking error: Does fund accurately track index?
3. Regional allocation: Need overseas exposure?
Bogle's quote: "Don't look for the needle in the haystack. Just buy the haystack."
After Bogle-style analysis, what should I do next?
1️⃣ Choose 1-3 low-cost index funds (broad market like CSI 300, S&P 500)
2️⃣ Set fixed monthly investment date
3️⃣ Don't watch market, don't time, don't switch funds
4️⃣ Rebalance only once annually
5️⃣ Stick with it for 10+ years
Bogle's data: Long-term, 90%+ active funds underperform index. Your goal isn't "beating the market" but "not losing to the market".