How does an inverse floater work and why does it have leveraged exposure to interest rate changes?

An inverse floater is a structured note whose coupon rate moves inversely to a reference rate. As rates fall, the coupon rises, and vice versa. The leverage comes from the multiplier (L) and the structure's creation from a fixed-rate bond.

Coupon Formula:

Coupon = K - L x Reference Rate

Where:

• K = Maximum coupon rate (cap)
• L = Leverage factor (multiplier)
• Reference rate = SOFR, EURIBOR, etc.
• Floor at 0% (coupon cannot go negative)

Creation From a Fixed-Rate Bond:

An inverse floater is created by splitting a fixed-rate bond into a regular floater and an inverse floater:

Fixed-rate bond → Floater + Inverse Floater

If a $100M, 6% fixed bond is split into a $75M floater and $25M inverse floater:

• Floater coupon: SOFR
• Inverse floater must ensure total interest = 6% of $100M = $6M
• $75M x SOFR + $25M x Inverse coupon = $6M
• Inverse coupon = ($6M - $75M x SOFR) / $25M = 24% - 3 x SOFR

The leverage factor is 3x because the inverse floater is 1/4 of the total, so it must absorb all the rate variability for the larger pool.

Example — Rate Scenarios:

Why Leveraged Duration:

Duration of inverse floater = (1 + L) x Duration of underlying fixed bond

If the 6% fixed bond has duration of 7.5 years:

• Inverse floater duration = (1 + 3) x 7.5 = 30 years

This means a 100 bps rate increase causes approximately a 30% price decline — extreme leverage.

Who Uses Inverse Floaters?

1. Bullish on rates falling: Investors who strongly believe rates will decline
2. Duration extension: Portfolio managers who need to dramatically increase duration without adding new capital
3. Structured notes: Banks embed inverse floater features in retail notes

Key Risks:

• Zero floor: When rates rise enough, coupon drops to zero and the investor holds an effectively zero-coupon long-duration bond
• Extreme price volatility: 3x leveraged duration means 3x the price swings
• Liquidity: Inverse floaters are thinly traded

CFA Exam Focus: Know the coupon formula, understand the leverage mechanism, and be able to calculate effective duration of an inverse floater.

For more structured products analysis, check our CFA fixed income course.