Portfolio a alokace
Building a Portfolio for a Large Lump Sum
Key takeaways
- Statistically, investing a large amount all at once (lump sum) wins — markets rise on more days than they fall.
- Psychologically, spreading the entry over 6–12 months with regular contributions is often easier.
- The longer the horizon, the less the precise entry timing matters.
- The worst strategy: leaving money sitting in a current account and waiting for the "right moment".
A large lump sum — from an inheritance, property sale, or bonus — requires a different approach than monthly saving: the psychological pressure is higher and the entry point has a greater impact on the overall outcome.
Lump Sum vs. DCA: What the Data Say
Academic studies repeatedly show that investing the full amount at once (lump sum) outperforms gradual entry (DCA) on average. The logic is simple: markets rise on more days than they fall, so time spent out of the market costs returns.
On average, a lump sum wins in roughly two-thirds of cases over a three-year horizon. But the remaining third — buying just before a downturn — is psychologically very painful.
When DCA Makes Sense
A gradual entry (DCA) over 6–12 months makes sense if:
- you're psychologically unable to invest everything at once and know you'd sell during a downturn;
- the horizon is shorter and volatility is therefore a real problem;
- you have enough other assets and this sum is a supplement rather than the foundation of your portfolio.
How to Build a Portfolio for a Large Sum
First, clarify your goal and horizon — see investing for a specific goal. Then set your allocation. For a long horizon (10+ years), a fully equity portfolio may be appropriate. For a shorter horizon, add bonds or savings products for the portion needed soon.
Practical Steps
Choose an ETF matching your allocation, select a broker suited to Czech residents, and be aware that the first year will be psychologically the hardest. Volatility won't disappear — but time in the market gives you more chances at returns than trying to achieve a perfect entry.
FAQ
Is it better to invest a large amount all at once or gradually?
Statistically, lump sum wins in roughly two-thirds of cases because markets rise on more days than they fall. Psychologically, spreading the entry over 6–12 months may be more comfortable — both approaches are valid, but waiting years for the "right moment" is the worst choice.
How long should I spread the entry of a large sum?
Typically 3–12 months is enough for psychological comfort. A longer spread (2+ years) statistically significantly reduces the probability of outperforming an immediate lump sum entry, because the money stays out of the market too long.
What should I do with the money while I'm investing it gradually?
Keep the uninvested portion in a liquid and conservative instrument — a savings account or government treasury bills. Minimise the time in cash or in a current account earning no interest at all.