The Best Investment Writing Volume 4: Selected Writing from Prominent Investors and Authors

Episode Summary

Executive Summary: This episode is a compilation of investment research readings on major portfolio themes: U.S. home bias risk, negative-yielding bonds and currency hedging, bubble/anti-bubble identification, revenue-based geographic diversification, stock market bubble dynamics, and the power of bond convexity. Across the pieces, speakers argue that valuations, sentiment, and hidden exposures matter more than domicile labels or headline yields, and that investors should favor diversification, avoid concentrated bubble assets, and understand how rates and currencies change real returns.

Main Topics: U.S. home bias and hidden active risk: MSCI’s Anil Rao argues that overweighting U.S. equities in model portfolios adds substantial tracking error and can create a long cycle of relative outperformance that eventually reverses. Negative-yield bonds and currency-hedged carry: Vineer Bansali explains how foreign bonds with negative nominal yields can become positive-yielding for dollar investors once currency hedges are added, but warns this is a fragile carry trade dependent on central bank policy and rate differentials. Bubble and anti-bubble framework: Rob Arnott defines bubbles and anti-bubbles using valuation plus investor behavior, then applies the framework to mega-cap tech, crypto, Tesla, UK equities, and emerging-market SOEs. Revenue exposure vs domicile for geographic diversification: Morningstar’s Alec Lucas shows that company headquarters can misrepresent true economic exposure and that revenue-based measures provide a better view of geographic concentration and diversification. A quantitative model of stock market bubbles: GMO’s Martin Tarlie presents a model where bubbles emerge when valuations are high and sentiment is improving, then burst when sentiment changes direction, producing sharp mean reversion and higher volatility. Bond convexity at low rates: Portfolio Charts’ Tyler shows that bond returns become increasingly convex as yields fall, meaning long-duration bonds can offer surprising upside even from already-low or negative rates, though with greater volatility.

Key Arguments: A U.S. equity home bias adds meaningful active risk before any tactical tilts or active managers are layered on top, making home-country concentration an independent portfolio risk. Currency-hedged foreign bonds may appear unattractive on a local-currency basis but can deliver positive carry to foreign investors because the forward hedge embeds interest-rate differentials. Negative-yield bonds are not necessarily long-term investments; their apparent attractiveness often depends on finding a greater fool before principal loss or yield erosion shows up. Bubble conditions require both expensive valuations and a speculative, narrative-driven buyer base; anti-bubbles are the mirror image, where assets are so cheap that only implausibly bad outcomes would justify current prices. Market-cap-weighted indexes mechanically increase exposure to the most expensive, most popular names, which can amplify bubble exposure without investors consciously choosing to take that bet. Revenue exposure is often a better measure of true geographic risk than domicile, because multinationals earn cash flows far from where they are listed or headquartered. Bubble bursts are hard to time because the catalyst is not the level of sentiment but the change in sentiment; once hopes for further improvement fade, mean reversion can be abrupt. Long-duration bonds at very low rates can still generate large gains because bond price sensitivity accelerates as yields fall; low rates do not eliminate fixed-income upside. Investors should use valuation and exposure analysis to avoid overpriced assets and seek unloved but fundamentally attractive markets or sectors. Diversification should be judged by economic exposure, not just by listing location or benchmark domicile, especially in a globalized corporate landscape.

Data Points: Active risk from U.S. home bias: Over 70 basis points - MSCI example showing a 15% U.S. equity overweight added tracking error versus a no-home-bias reference portfolio. Home-bias allocation: 60% equity / 40% fixed income - Reference and biased model portfolios used to compare active risk. U.S. overweight in home-biased model: 15% overweight to U.S. equities - Funded by underweights to international and emerging-market stocks. Underweight to international stocks: 10% - Part of the home-biased allocation example. Underweight to emerging-market stocks: 5% - Part of the home-biased allocation example. Three-year drawdown example: U.S. home bias fell behind international by 20% - During the dot-com and financial-crisis era period highlighted in the MSCI piece. Five-year performance gap: 70 bps annual lag - Home-biased allocation trailed the reference allocation over a five-year period. Active risk in that five-year period: 100 bps - Comparable to the home-bias risk shown in the initial exhibit. Global government bonds trading negative: Almost 10 trillion worth - As cited in the discussion of negative-yielding bonds; narrator notes it later rose toward 20 trillion. Yield differential used in hedge example: About 3 cents per euro / about 3% - Illustrative USD/EUR forward premium creating positive carry for dollar investors hedging euro bonds. German 10-year yield example: Negative 25 bps local yield; about 2.75% hedged yield - Example showing a negative-yielding bond becoming positive yield for a U.S. investor. German 3-month yield example: Negative 50 bps; about 2.5% hedged yield - Illustrates how short maturities can also turn positive when hedged. German 2-year yield example: About 2.3% hedged yield - Hedged yield example from the same analysis. U.S. Treasury hedged from euro perspective: Negative 83 bps - A positive U.S. yield becomes negative for a euro-based investor after hedging. Japanese yen investor comparison: U.S. Treasuries were the worst hedged yield of the group - Shows how currency hedging can reverse relative attractiveness across currencies. SOE basket dividend yield: 4.2% - Top 50 emerging-market state-owned enterprises identified as an anti-bubble opportunity. Emerging Markets Index dividend yield: 2.75% - Benchmark comparison to SOE basket. MSCI ACWI dividend yield: 2.5% - Broader world benchmark cited alongside EM comparisons. SOE basket price-to-book: 1.03 - Valuation measure for the top 50 emerging-market state-owned enterprises. EM Index price-to-book: 1.61 - Compared against the SOE basket. SOE basket P/E: 8.9 - Valuation measure for the SOE basket. EM Index P/E: 13.5 - Broader benchmark valuation for comparison. UK index dividend yield: 4.5% - Used to support the UK anti-bubble argument amid Brexit uncertainty. UK index P/E discount: 25% discount to MSCI World - Part of the Brexit-related anti-bubble case. U.S. revenue share in MSCI ACWI: 41.9% - Revenue-based weighting in Morningstar’s geographic exposure analysis. China domicile vs revenue share: 3.5% domicile weighting vs 10.6% revenue weighting - Shows how revenue exposure can greatly exceed domicile exposure. Japan revenue share in MSCI ACWI: 7.2% - Compared with U.S. and China in revenue-based exposure. Australia ASX 200 home revenue share: 57.9% - Compared with the S&P 500’s high domestic revenue concentration. S&P 500 U.S. revenue share: 62% - Illustrates strong revenue-based home-country bias. CAC 40 home revenue share: 17.5% - Example of a lower domestic revenue concentration among French stocks. Russell 1000 weight in FanMag: Over 14% - Concentration measure cited in the bubble discussion. FanMag contribution to Russell 1000 returns: Nearly 40% - These six stocks accounted for a disproportionate share of index returns over the period discussed. Average FanMag return over period: Just over 40% - Describes the magnitude of the rally contributing to index concentration. FanMag decline in Q4 2018: Average loss of 21% - Temporary correction in high-flying tech names. Cryptocurrency peak market cap: $828 billion - Early January 2018 peak before a major selloff. Cryptocurrency market cap trough: $125 billion - End-of-2018 level after the selloff. Crypto drawdown: 84% - Aggregate drop from peak to trough. Crypto recovery in H1 2019: 187% - Rebound cited while arguing bubble conditions still remained. Tesla share price decline in first half of 2019: 32% to $223 - Used as evidence of fading bubble enthusiasm. 2018 EPS growth: 28% - Strong fundamental backdrop in the GMO bubble model. 2019 expected EPS growth: 12% - Expected slowdown that coincided with a negative shift in sentiment. 2019 EPS revision: Down more than 4% from August to December 2018 - Evidence of deteriorating expectations. US stock market valuation peak comparison: Matched 1929; exceeded only by late-1990s dot-com era - Used to frame bubble risk despite lack of obvious euphoria. Explosive-dynamics periods since 1881: Five - Late 1910s, 1929, early 1980s, late 1990s, and 2017-2018. Bond duration example: 7.4 years - Effective duration for the Intermediate-Term Treasury fund IEF. Weighted average coupon example: About 2.5% - Used in the convexity explanation for IEF. Weighted average maturity example: About 8.3 years - Used in the convexity explanation for IEF. 30-year bond return at 10% starting yield after 1% fall: About 20% total return - Illustrates convexity-driven upside from falling rates. 30-year bond return at -1% starting yield after 1% fall: About 40% total return - Shows how low/negative starting yields can magnify gains. 30-year bond return range at 0% starting yield: About -25% to +35% - Range of outcomes for a 1% rate move, highlighting volatility.

Pivotal Quotes: "Home bias alone added over 70 basis points of active risk." — Anil Rao: Explains the portfolio cost of overweighting U.S. equities relative to a global benchmark. "The currency hedge tail is indeed wagging the so-called bond dog." — Vineer Bansali: Describes how FX hedging, not bond coupons, can dominate returns in negatively yielding bond markets. "The market can remain irrational far longer than you can remain solvent." — Rob Arnott: Used to emphasize that bubble assets can stay expensive longer than investors expect.

Implications: Investors should look beyond labels like “U.S.” or “government bond,” and instead assess true exposure, valuation, and hedged returns. Concentration, sentiment shifts, and rate/currency changes can quickly reverse seemingly safe bets.