Simulate Your Monthly ETF Investment
Key Takeaways
- ▸Dollar-cost averaging (DCA) eliminates the need to time the market — you buy more shares when prices are low and fewer when high.
- ▸Regular monthly investing turns market volatility from a threat into an advantage over long time horizons.
- ▸Compound growth on recurring contributions accelerates dramatically in the final years of the investment period.
- ▸Consistency beats the size of individual contributions — small amounts invested every month outperform sporadic lump sums for most investors.
A Piano di Accumulo Capitale (PAC) — known internationally as a savings plan or dollar-cost averaging (DCA) strategy — is the practice of investing a fixed amount at regular intervals, regardless of market conditions. It is one of the most effective and psychologically sustainable approaches to long-term wealth building.
This simulator shows you the projected growth of your monthly ETF contributions over time, factoring in compound returns, annual fees, and inflation. Adjust the monthly amount, expected annual return, and investment period to explore different scenarios.
How Dollar-Cost Averaging Works
When you invest a fixed euro amount each month, you automatically buy more ETF units when the price is low and fewer when the price is high. Over time this produces an average purchase price that is typically lower than the arithmetic average price — a mathematical effect called dollar-cost averaging. This removes the impossible task of identifying the perfect moment to invest. Studies consistently show that even professional investors fail to time the market reliably over long periods, making DCA a rational strategy for retail investors who have neither the time nor the tools to predict short-term price movements.
Monthly Investing vs. Lump Sum
Mathematically, investing a lump sum immediately outperforms DCA on average — because markets rise more often than they fall, and a larger amount invested earlier benefits from more years of compound growth. However, this advantage is meaningful only if you actually have a large lump sum available and the emotional fortitude to invest it all at once during market uncertainty. In practice, most investors earn income monthly and invest what is left after expenses. For these investors, monthly DCA is not just practical — it is optimal. The psychological benefit of avoiding large single purchases during peaks is also significant: investors who use DCA are less likely to panic-sell during downturns.
ETF Monthly Investment Simulator
Dollar-Cost Averaging (DCA) Projection
Track Your Real Portfolio
Import your broker data and monitor your investments automatically.
Try DonkyCapital FreeThe Power of Compound Growth Over Time
The most counterintuitive aspect of long-term investing is that the majority of the final portfolio value is typically generated in the last third of the investment period. A monthly contribution of €300 invested for 30 years at 7% annual return produces a portfolio of around €340,000 — but €200,000 of that growth occurs in the final 10 years. This acceleration is the snowball effect of compounding: returns generate returns, which generate more returns. The implication is that small contributions started early are far more valuable than large contributions started late. Starting with €100 per month at age 25 beats starting with €500 per month at age 45 in the same scenario.
Frequently Asked Questions
What is a PAC and how does it work?
A PAC (Piano di Accumulo Capitale) is the Italian term for a regular investment plan, equivalent to the international concept of dollar-cost averaging (DCA). You invest a fixed amount — for example €200 per month — into one or more ETFs on a set schedule, regardless of whether markets are up or down. Over time this creates a diversified portfolio with an averaged purchase cost.
Is lump sum investing better than monthly DCA?
In theory, lump sum investing produces higher expected returns because markets trend upward over time and investing all at once maximizes time in the market. In practice, most people do not have a large idle lump sum available and psychologically find it very difficult to invest everything at once. For regular earners who invest from monthly income, DCA is the optimal and natural approach.
Which ETFs are best for a monthly investment plan?
Broad global equity ETFs — such as those tracking the MSCI World, MSCI ACWI, or FTSE All-World indices — are the most commonly recommended for long-term DCA plans. They offer maximum diversification across thousands of companies and geographies. Adding a bond ETF to reduce volatility is useful for investors closer to their withdrawal horizon. Keep the number of ETFs small — 1 to 3 is sufficient for most investors.
How much should I invest each month?
The standard personal finance guidance is to invest at least 10–20% of your net income. More importantly, the amount should be sustainable — a commitment you can maintain through market downturns without interruption. Use the simulator to work backwards: decide on your target portfolio value and timeline, then calculate the monthly contribution needed. Start with what you can and increase the amount annually as your income grows.
What happens to my DCA plan during a market crash?
Market crashes are the moment when DCA delivers its greatest advantage. When prices fall sharply, your fixed monthly contribution buys significantly more ETF units than usual. When the market recovers, those cheaply acquired units generate outsized gains. The key is to continue contributing during downturns rather than stopping or reducing contributions — which is the most common and costly behavioral mistake retail investors make.
Track Your PAC Progress in Real Time
Connect your broker to DonkyCapital and see how your monthly investment plan is performing — including total contributions, current value, and projected growth — all in one dashboard.
Try DonkyCapital Free