Constant Proportion Portfolio Insurance (CPPI)
Constant Proportion Portfolio Insurance (CPPI) is a dynamic portfolio strategy that maintains a minimum portfolio floor value by allocating between a risky asset and a safe asset using a fixed multiplier applied to the cushion above the floor.
CPPI is a rules-based capital protection strategy designed to guarantee a minimum terminal value (the floor) while still participating in equity market upside. The framework was developed in the 1980s by Fischer Black and Robert Jones and has since been adapted widely, including within Indian structured products and capital protection-oriented mutual funds.
The mechanics are straightforward. Define a floor F — the minimum acceptable portfolio value at the horizon. The cushion C equals the current portfolio value P minus the floor: C = P − F. The allocation to the risky asset (typically equity) equals the multiplier m times the cushion: Equity Exposure = m × C. The remainder is invested in a safe asset (government bonds, liquid funds). As the portfolio grows, the cushion widens and equity exposure rises; as the portfolio falls toward the floor, the cushion shrinks and the manager de-risks aggressively, potentially moving to 100% safe assets.
The multiplier m is the key parameter. A higher multiplier (e.g., 5) amplifies equity participation but also increases the speed of de-risking in falling markets. If the market falls so rapidly that the portfolio breaches the floor before de-risking can occur — a gap risk — the guarantee fails. This is the principal weakness of CPPI in crash environments.
In India, SEBI's category of capital protection-oriented funds follows CPPI logic, though the exact parameters vary by fund house. These closed-ended schemes typically offered 3–5 year tenors, with the floor set at the initial investment amount, ensuring capital protection at maturity. Franklin Templeton and ICICI Prudential had launched such structures in India in earlier years. The strategy also appeared in principal-protected structured notes marketed to HNI investors through SEBI-registered distribution channels.
CPPI is distinct from option-based portfolio insurance (OBPI), which uses put options to set the floor. CPPI avoids option premiums but incurs transaction costs from frequent rebalancing and suffers from gap risk in illiquid or crash scenarios. In Indian markets, high-frequency crashes (such as the March 2020 episode where Nifty fell over 13% in a single day) highlighted the practical limitations of CPPI when gap risk materialises.