Compounding Illustration (Indian Context)
A monthly SIP of ₹10,000 at 12% CAGR grows to approximately ₹23 lakh in 10 years, ₹99 lakh in 20 years, and ₹3.5 crore in 30 years — illustrating how time, consistency, and a reasonable return assumption can transform modest monthly savings into life-changing wealth through the power of compounding.
Albert Einstein is often (apocryphally) credited with calling compound interest the eighth wonder of the world. Whether or not he said it, the mathematics of compounding in the Indian context deserves careful examination — because the numbers are genuinely transformative.
THE BASIC FORMULA: Future Value of SIP = P × [((1 + r)^n - 1) / r] × (1 + r), where P is the monthly investment, r is the monthly return rate, and n is the number of months.
SCENARIO TABLE (₹10,000/month at 12% CAGR): - 10 years: Total invested ₹12 lakh → Corpus ₹23.2 lakh → Gain ₹11.2 lakh - 20 years: Total invested ₹24 lakh → Corpus ₹99.9 lakh → Gain ₹75.9 lakh - 30 years: Total invested ₹36 lakh → Corpus ₹3.53 crore → Gain ₹3.17 crore
At 30 years, the investor has contributed only 10% of the final corpus — compounding generates the remaining 90%. This is the essence of long-term equity investing.
IMPACT OF RATE ASSUMPTION: At 10% CAGR, the 30-year corpus is ₹2.27 crore. At 14% CAGR, it is ₹5.34 crore. A 4% difference in return translates to a 2.4x difference in terminal wealth over 30 years — highlighting the importance of cost-efficient investing (low-expense-ratio funds).
IMPACT OF STARTING EARLY: A 25-year-old investing ₹10,000/month for 30 years accumulates ₹3.53 crore by age 55. A 35-year-old investing the same for 20 years accumulates only ₹99 lakh by age 55 — despite only 10 years difference in start time, the wealth is 3.5x higher for the early starter.
INFLATION ADJUSTMENT: In real (inflation-adjusted) terms at 6% inflation, the 30-year corpus of ₹3.53 crore is worth approximately ₹61 lakh in today's purchasing power — still more than 5x the amount invested.
SECOND-ORDER COMPOUNDING: Reinvested dividends add meaningfully. A total return (price + dividend reinvestment) assumption adds 1-2% to annual returns, compounding significantly over 20-30 years.
The compounding story is the single most powerful argument for starting equity investing early and staying invested through market volatility.