Partial Annuitization vs the 4% Rule

New US retirement research tested four income strategies across >10K simulated life paths, factoring taxes, health premiums, distribution rules, and claiming choices.
The strongest result favored partial annuitization: converting some savings into lifetime income while keeping the rest invested outperformed withdrawal-only and fully annuitized approaches.
For a 65-yr single woman with $1M, a one-time half annuity purchase ranked first, with gradual annuitization close behind in utility scores.
The withdrawal-only approach showed the weakest income and rising depletion risk, with assets exhausted before death in nearly 1 in 8 cases by age 90.
Bridging to age 70 improved the baseline retiree's results across all strategies, but some later or legacy-focused retirees benefited more from claiming sooner.