Strategies/ Deep Dive
Strategies · Deep Dive 7 min read

Dollar-Cost Averaging

Why Not Just Invest It All at Once?

If you had a lump sum today, investing all of it immediately is actually the mathematically optimal move on average, since markets tend to rise over time. But most people aren't investing a lump sum — they're investing from a monthly paycheck. Dollar-cost averaging (DCA) just means committing to invest the same amount on a set schedule, regardless of whether prices are up or down that month.

  • The mechanic. A fixed AED amount buys more shares/units when the price is low, and fewer when the price is high — automatically, without you having to guess anything.
  • What it actually protects against. Not bad returns — it protects against the psychological trap of trying to "wait for the right moment," which usually just means waiting indefinitely.
  • What it doesn't do. It doesn't guarantee a better outcome than investing a lump sum — if prices mostly go up in a straight line, buying everything on day one would have won.
Example

Say you invest AED 500 a month into a fund over four choppy months, at prices of AED 50, then 40, then 45, then 55 per unit. Month 1: AED 500 ÷ 50 = 10 units. Month 2: AED 500 ÷ 40 = 12.5 units. Month 3: AED 500 ÷ 45 ≈ 11.11 units. Month 4: AED 500 ÷ 55 ≈ 9.09 units. Total: about 42.7 units for AED 2,000 spent — an average cost of roughly AED 46.84 per unit. Compare that to putting the full AED 2,000 in on day one at AED 50 per unit: exactly 40 units. In this particular case, spreading it out bought you 2.7 extra units for the same money, simply because you kept buying through the dip in months 2 and 3.

The Honest Trade-Off

This example makes DCA look like a clear win, but that's only because prices dipped in the middle. If prices had instead gone AED 50, 55, 60, 65 — straight up — investing the full AED 2,000 on day one at AED 50 would have beaten DCA every time. Nobody knows in advance which pattern will happen. What DCA really offers isn't a guaranteed edge — it's a way to keep investing consistently without needing to predict anything, which for most people beats the alternative of waiting for a "better" moment that may never come.

The Short Version

Investing a fixed amount on a regular schedule — instead of trying to time the market — so your purchase price ends up averaged out over the highs and the lows.