Why your allocation decides everything after 25 years

There is a widespread belief in the world of investing: what matters is picking the right securities. The right stocks, the right funds, the right managers. The data shows this belief is almost entirely wrong. What determines your outcome over the long term is mainly one single decision, often made in five minutes and rarely revisited: your asset allocation.

What is asset allocation?

Asset allocation is the split of your capital across the major investment classes. In its simplest form: equities (shares in listed companies), bonds (loans to governments or companies), and cash (savings, money market accounts). Some investors add real estate or commodities, but the first three categories cover the vast majority of retail financial wealth.

Concrete example: if you have CHF 100'000 invested and CHF 60'000 are in equities, CHF 30'000 in bonds, and CHF 10'000 in a savings account, your allocation is 60/30/10.

This decision can seem technical, almost administrative. Yet it is the most structurally important one you will make in wealth management.

The numbers: what allocation does to your wealth over 25 years

Take an investor with CHF 100'000 starting capital and CHF 1'000 monthly contributions, over a 25-year horizon. Consider four typical allocations:

• Conservative: 20% equities, 60% bonds, 20% cash
• Balanced: 60% equities, 30% bonds, 10% cash
• Dynamic: 80% equities, 15% bonds, 5% cash
• 100% equities: 100% equities, 0% bonds, 0% cash

Using long-term historical return assumptions (equities: 6.8%, bonds: 2.5%, cash: 0%), the median of 1'500 Monte Carlo trajectories after 25 years gives:

• Conservative (20/60/20): median wealth approximately CHF 630'000
• Balanced (60/30/10): median wealth approximately CHF 840'000
• Dynamic (80/15/5): median wealth approximately CHF 940'000
• 100% equities: median wealth approximately CHF 1'040'000

The gap between the conservative profile and the 100% equity profile is over CHF 400'000, 65% more, for the same total amount invested (CHF 100'000 + CHF 1'000 × 12 × 25 = CHF 400'000). That is what allocation does to final wealth.

Explore these gaps yourself in the ViaVest allocation simulator: adjust the parameters and visualise each profile.

The paradox of the conservative profile

Many investors choose a conservative profile out of fear of volatility. The reasoning is natural: equities can lose 40% in a year (as in 2008), which is uncomfortable. So you reduce the equity share.

What is underestimated is what this reasoning costs over the long term. By choosing the conservative rather than the balanced profile, you statistically "forgo" around CHF 210'000 of wealth over 25 years. That is the real cost of this "safety".

The question therefore is not "which allocation feels comfortable?", but "what level of annual volatility can I actually tolerate without panic-selling?" If you can see your portfolio fall 25 to 30% one year and hold the course while continuing to invest, a more dynamic profile is probably justified over 20+ years.

Volatility is not risk, it is the engine

There is a fundamental confusion between volatility and risk. Volatility is short-term value fluctuation. Risk, for a long-term investor, is failing to reach wealth objectives.

Over a 25-year horizon, the global equity market (MSCI World) has never produced a negative return over the full period. Academic studies show that beyond 15 to 20 years of holding, the probability of a positive return on diversified global equities approaches 95 to 99%. Annual volatility is high, but long-term returns are structurally positive.

A 100% bond portfolio may seem less "risky" year to year, but over 25 years it produces a far inferior result. The "risk" of not building the target wealth is significantly higher with this profile.

What allocation cannot do for you

Asset allocation does not protect against a severe bear market. In 2008-2009, a 60/40 portfolio lost approximately 25 to 30% in a few months. In 2022, rising rates caused equities and bonds to fall simultaneously, the famous "60/40 crash". There is no magic allocation that always grows.

What allocation does: it calibrates the ratio between long-term expected gain and short-term shock amplitude. An 80% equity profile will have harder years (-40% is possible) but a significantly higher long-term median than a 30% equity profile.

Allocation and the 2nd pillar: your actual profile is probably more conservative than you think

A frequently ignored point: your 2nd pillar (BVG) is itself a de facto bond-like asset. BVG capital grows at the legal minimum rate (1.25% in 2026) and is converted into a lifetime pension at retirement, which functionally resembles a long-duration bond.

For a typical Swiss employee, the 2nd pillar represents 20 to 40% of total wealth at retirement. If your pension fund invests 30 to 40% in bonds (which is common), and you add your 2nd pillar, your actual allocation is probably already significantly more conservative than your financial portfolio suggests.

This argues for a higher equity share in the personal financial portfolio, for those who want a genuinely diversified overall allocation.

How to decide your allocation

There is no universal answer. But here are the useful questions:

• What is your actual horizon? If you need the capital in 5 years, a high equity share is risky. If it is in 25 years, bear market phases barely change anything.
• Can you hold through a 30% decline? This question is more important than any return table. Many people "know" they can hold, but sell at the worst moment in practice.
• What other assets do you have? Real estate, 2nd pillar, 3rd pillar. The financial portfolio allocation is not decided independently of the rest of your wealth.
• Do you have a stable income? A civil servant with guaranteed income can afford a more dynamic profile than a self-employed person with variable income.

Allocation is a decision, not a permanent setting

Contrary to what many think, allocation is not fixed for life. It should evolve with your situation and horizon. A common rule of thumb suggests progressively reducing the equity share approaching retirement, to limit "sequence risk" (a severe bear market in the first years of retirement can have lasting consequences).

In practice, this might mean: 80% equities at 35, 70% at 45, 60% at 55, 50% at 65. Every situation is different, but the direction is clear: reduce volatility as the horizon shortens.

Conclusion

Asset allocation is not technically complex. It is psychologically difficult: accepting short-term volatility in exchange for a statistically superior long-term outcome, without knowing with certainty what the future holds.

Historical data and Monte Carlo simulations consistently show that over 20 to 30-year horizons, allocation is the primary driver of outcomes. Choosing too conservative a profile out of fear of equities can cost several hundred thousand francs of final wealth.

To explore the numbers yourself with your personal parameters, the ViaVest asset allocation simulator is available below.