Herweging

What Is Herweging?

Herweging, also known as rebalancing, is the process of realigning a portfolio's asset allocation back to its original or target weights. This strategy falls under the broader financial category of portefeuillebeheer (portfolio management). Over time, different asset classes within an investment portfolio will experience varying rates of rendement, causing the portfolio's actual allocation to drift away from the investor's intended mix. Herweging involves selling assets that have outperformed and now represent a larger percentage of the portfolio, and using those proceeds to buy assets that have underperformed or grown less, bringing the portfolio back to its predetermined vermogensallocatie. This disciplined approach helps maintain the desired risicotolerantie and ensures the portfolio remains aligned with an investor's beleggingsdoelstellingen.

History and Origin

The concept of rebalancing is deeply rooted in modern portfolio theory, which emerged in the mid-20th century. As investment strategies evolved beyond simply picking individual securities, the focus shifted to managing a collection of assets. Early proponents of diversified portfolios understood that market fluctuations would inevitably cause the initial asset mix to drift. The practice of regularly restoring a portfolio to its target allocation gained prominence as a way to control risk and maintain a consistent investment approach. While there isn't a single definitive "inventor" of rebalancing, its importance has been consistently highlighted in academic and practitioner literature focused on long-term investment strategies. For instance, research by entities like Vanguard has explored how different rebalancing approaches can help maintain a portfolio's risk-and-return characteristics over time.¹⁹

Key Takeaways

• Herweging (rebalancing) is the systematic process of adjusting a portfolio's asset weights back to their target allocation.
• Its primary goal is to manage portfolio risk, ensuring it remains consistent with the investor's predetermined risicotolerantie.
• Rebalancing can involve selling appreciated assets and buying underperforming ones, effectively implementing a "buy low, sell high" discipline.¹⁸
• The frequency of herweging can be time-based (e.g., annually) or threshold-based (e.g., when an asset deviates by a certain percentage).¹⁷
• It is a crucial component of a disciplined beleggingsstrategie, especially for lange termijn beleggen.

Interpreting Herweging

Interpreting rebalancing centers on understanding its role in managing a portfolio's long-term risk and return profile rather than short-term market timing. The act of herweging is not about predicting market movements but about adhering to a predefined beleggingsstrategie. If a portfolio's equity component grows significantly due to a bull market, its overall risk level increases. Rebalancing reduces this exposure to higher-risk assets, aligning the portfolio with the investor's original risico-rendementverhouding.

Investors can choose different approaches for rebalancing:

• Time-based rebalancing involves reviewing and adjusting the portfolio at set intervals (e.g., quarterly, annually). This method is straightforward and helps automate the process.¹⁶
• Threshold-based rebalancing triggers an adjustment only when an asset class deviates from its target weight by a predefined percentage (e.g., 5% or 10%).¹⁵ This approach might lead to less frequent trading in stable markets but more frequent trading during periods of high marktvolatiliteit.

Many investors, particularly those following a passief beheer strategy with indexfondsen, find a combination of these methods effective.¹⁴ The goal is to maintain the intended vermogensallocatie without excessive trading that could incur unnecessary kosten.

Hypothetical Example

Consider an investor, Maria, who establishes a portfolio with a target asset allocation of 60% stocks and 40% bonds, aligning with her risicotolerantie. She invests €100,000, with €60,000 in stocks and €40,000 in bonds.

After one year, the stock market performs exceptionally well, and Maria's stock holdings increase in value by 25%, while her bond holdings only increase by 5%.

• Stocks: €60,000 * 1.25 = €75,000
• Bonds: €40,000 * 1.05 = €42,000
• Total Portfolio Value: €75,000 + €42,000 = €117,000

Now, let's calculate the current allocation:

• Current Stock Allocation: (€75,000 / €117,000) * 100% ≈ 64.10%
• Current Bond Allocation: (€42,000 / €117,000) * 100% ≈ 35.90%

Maria's portfolio has drifted from her 60/40 target to approximately 64/36. To perform herweging, she would sell stocks and buy bonds to bring the allocation back to 60/40.

• Target Stock Value: €117,000 * 0.60 = €70,200
• Target Bond Value: €117,000 * 0.40 = €46,800

To rebalance, Maria would sell €75,000 - €70,200 = €4,800 worth of stocks and use that €4,800 to buy additional bonds (€42,000 + €4,800 = €46,800). This action realigns her portfolio with her initial beleggingsdoelstellingen and desired risk exposure.

Practical Applications

Herweging is a fundamental practice across various aspects of investing and financial planning:

• Retirement Planning: Investors often adopt a "glide path" approach for retirement portfolios, which involves gradually shifting towards more conservative assets as retirement approaches. Regular herweging is essential to ensure the portfolio remains on this path and adjusts to changing time horizons.
• Fund Management: Professional fund managers, especially those managing target-date funds, systematically rebalance their portfolios to adhere to their stated investment objectives and risk profiles. These funds often use both calendar-based and threshold-based rebalancing to manage portfolio drift.
• Risk Management: By routinely bringing asset ¹³weights back to target, herweging acts as a core risk management tool, preventing any single asset class from dominating the portfolio due to strong performance and disproportionately increasing overall portfolio risk. Maintaining a disciplined diversificatie strategy through rebalancing helps smooth out the ups and downs of an overall portfolio. The Financial Industry Regulatory Authority (FINRA) e¹²mphasizes that maintaining a disciplined investment strategy, which includes periodic review and adjustments, is crucial for investors.

Limitations and Criticisms

While generally consi¹¹dered a sound practice, herweging is not without its limitations and criticisms:

• Transaction Costs and Taxes: Frequent rebalancing can lead to increased kosten through brokerage commissions and bid-ask spreads. Furthermore, in taxable accounts, selling appreciated¹⁰ assets to rebalance can trigger capital gains taxes, potentially eroding rendement. Investors often prefer to rebalance within tax-advant⁹aged accounts like 401(k)s or IRAs to avoid immediate tax implications.
• Missing Out on Gains: In strong, sustained bu⁸ll markets, continuously selling winning assets to buy underperforming ones (as required by herweging) might lead to lower overall returns compared to a "buy and hold" strategy, which allows winning assets to run. Some academic research has indicated that rebalancing benefits are not always large, and the strategy might forgo some gains, though it maintains relative safety.
• Complexity for Individual Investors: Determin⁷ing the optimal rebalancing frequency and method can be complex. While tools exist to help, the decision often requires careful consideration of an investor's specific circumstances, including their tax situation and liquiditeit needs. Research by institutions such as the National Bureau ⁶of Economic Research (NBER) has even highlighted that predictable rebalancing by large institutional investors can create market impacts, potentially allowing certain market participants to "front-run" these trades, leading to billions in annual costs for investors.

Herweging vs. Vermogensallocatie

Herweging (reba⁵lancing) and vermogensallocatie (asset allocation) are two interconnected but distinct concepts in portefeuillebeheer.

Vermogensallocatie refers to the strategic decision of how an investment portfolio is divided among different asset classes, such as stocks, bonds, and cash. This initial decision is based on an investor's beleggingsdoelstellingen, time horizon, and risicotolerantie. For example, a common asset allocation might be 60% stocks and 40% bonds. It's the blueprint for the portfolio.

Herweging, on the other hand, is the process of maintaining that predetermined vermogensallocatie over time. As market conditions change, asset classes perform differently, causing the actual weights of the portfolio components to drift away from the target allocation. Herweging is the active step taken to bring the portfolio back into alignment with its original blueprint. Without rebalancing, a portfolio's risk profile could unknowingly shift, becoming either more aggressive or more conservative than intended.

In essence, asset allocation is the "what" (the desired mix), and herweging is the "how" (the action taken to keep that mix consistent).

FAQs

Why is herweging important?

Herweging is crucial primarily for risicobeheer. Without it, a portfolio's exposure to certain asset classes can drift significantly from its original target, potentially increasing its overall risk level beyond what the investor is comfortable with. It helps maintain the intended risico-rendementverhouding.

How often should I rebalance my portfolio?

There's no single "best" frequency. Common approaches include calendar-based rebalancing (e.g., annually or semi-annually) or threshold-based rebalancing (e.g., when an asset class deviates by 5% or 10% from its target). Some investors combine both. The choice depends on in⁴dividual preferences, market marktvolatiliteit, and the potential for transaction kosten.

Does rebalancing improve investment returns?

The primary benefit of rebalancing is risk control rather than guaranteed higher returns. While it can, in some scenarios, lead to better risk-³adjusted returns by forcing investors to "buy low and sell high," its main purpose is to ensure the portfolio's risk profile remains aligned with the investor's objectives. In strongly trending markets, a "buy and hold" strate²gy might sometimes outperform in terms of raw returns, but it often comes with higher volatility.

Can I rebalance without incurring taxes?

Yes. Rebalancing is generally more tax-efficient within tax-deferred accounts like 401(k)s or IRAs, as buying and selling within these accounts does not trigger immediate capital gains taxes. For taxable accounts, investors might choose to rebal¹ance by directing new contributions to underweighted assets or by utilizing tax-loss harvesting strategies if applicable.