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Retirees tend to shift their spending patterns as needed throughout life, and will make cuts or increases if necessary.

The funded ratio: When retirement income projections are based on static spending rules, the result can lead to a significantly different withdrawal strategy than the reality of how that household might actually spend. Instead, Blanchett proposes utilizing funded ratio metrics to “estimate the overall financial situation of retiree consumption.”

The measurement is calculated by taking your total current and future value of assets, divided by all current or future expected spending. If the result is 1.0, you have just enough to fund your goal. Any more or less means you’re over or under-funded. Of course, there are considerations that play into income and spending, including duration of retirement, risk level and RMDs, but taking a more dynamic approach to how your spending could shift throughout your lifetime allows for a potentially more flexible, accurate withdrawal strategy.

If you need another sign that your retirement plan should be personalized to your unique situation, look no further. Don’t always believe rules of thumb; look inward.