Bond Tent (Glide Path) Calculator

Understanding the bond tent glide path calculator — concept and principle

A bond tent is an asset-allocation path that raises your bond share in the years before retirement and then lowers it again in the first years after. Plotted over time, it looks like a tent peaking at retirement. This calculator draws that path between three points you choose and shows how much of your portfolio would be in bonds at retirement.

How it is calculated

• Before retirement: bond % = starting % + (peak % − starting %) × (age − current age) ÷ (retirement age − current age)
• After retirement: bond % = peak % + (final % − peak %) × (years since retiring) ÷ 10, reaching the final % ten years after retirement
• Stock % = 100 − bond %
• Bonds at retirement = portfolio value × peak % ÷ 100

The table shows about five steps before retirement, then every two years.

The principle

The biggest danger for a new retiree is sequence-of-returns risk: a market crash in the first years, while you are already withdrawing, can permanently shrink the portfolio, even if average returns later are fine. Holding more bonds around the retirement date cushions that window. Once you are past it, research by Wade Pfau and Michael Kitces (2014) suggested that gradually moving back towards stocks, a rising equity glide path, could improve outcomes compared with a fixed or steadily falling stock share.

Worked example

1. Age 55, retirement at 65, bonds 30% now, peak 60%, 40% ten years after retiring, portfolio $900,000.
2. The pre-retirement rise is 30 points over 10 years, 3 points a year; steps are 2 years apart: age 57 → 36%, 59 → 42%, 61 → 48%, 63 → 54%, 65 → 60%.
3. After 65 the share falls 20 points over 10 years, 2 points a year: 67 → 56%, 69 → 52%, 71 → 48%, 73 → 44%, 75 → 40%.
4. Bonds at retirement = 900,000 × 60% = $540,000 (60% bonds, 40% stocks).

How to read the result

The peak tells you how much protection you hold at the riskiest moment. A common rule of thumb is to have several years of planned withdrawals in safer assets around retirement. The portfolio value is held constant here, so actual amounts in bonds will change as markets move; rebalance to the target percentages, not to dollar figures.

Common mistakes

• Making the tent too steep to execute without large taxable sales.
• Holding the peak forever and losing long-run growth.
• Ignoring guaranteed income such as pensions, which already act like bonds.

Frequently asked questions

Why reduce bonds after retiring?

The danger of a crash ruining the plan is greatest early; later, more stocks help the money keep up with inflation over a long retirement.

What counts as bonds?

Usually high-quality bonds and cash-like holdings.

Is ten years after retirement fixed?

In this calculator, yes; it is a common choice in research, but you can adjust the final percentage to suit you.

Sources: Pfau, W. D. & Kitces, M. E. (2014). Reducing Retirement Risk with a Rising Equity Glide Path. Journal of Financial Planning