Yearfold journal
Field notes on planning a real retirement
Every post links its sources. We update the year-stamp on the right whenever a post is reviewed against new data.
April 30, 2026 · The Yearfold team
Why your 401(k) projection is probably too optimistic
Brokerage retirement projections quietly skip three forms of risk. Here's what they leave out, and why your real-world result usually undershoots the line on the chart.
pillar · 401k · fundamentals
April 28, 2026 · The Yearfold team
What is the 4% rule, and is it still right in 2026?
Bengen's 4% safe-withdrawal rate, what the rule actually says, where the 2026 critiques land, and the safe range you can defend.
pillar · fundamentals · withdrawal
April 24, 2026 · The Yearfold team
Sequence-of-returns risk: the math that breaks retirement plans
Two retirees with identical 30-year average returns can have wildly different outcomes if the order of returns is different. Here's why, and what to do about it.
pillar · fundamentals · withdrawal
April 21, 2026 · The Yearfold team
Roth conversion ladders in 2026: when they pay, when they don't
A Roth conversion ladder can save high-income retirees six figures in lifetime taxes — or cost them the same if mistimed. Here's the math.
pillar · roth · taxes
April 17, 2026 · The Yearfold team
Medicare and IRMAA: the retirement cost most calculators miss
Healthcare is the biggest variable in retirement spending. Here's what Medicare actually costs in 2026, what IRMAA does to high-income retirees, and how to plan around both.
pillar · medicare · healthcare
April 15, 2026 · The Yearfold team
How much do I really need to retire? A 2026 reality check
The honest answer is a range, not a number — and the range depends on three things most rules of thumb skip.
pillar · fundamentals
April 8, 2026 · The Yearfold team
Social Security claim age: 62 vs 67 vs 70, with worked numbers
How much does waiting actually pay? Three workers, identical earnings histories, three claim ages. The gap is bigger than most people expect.
social-security · fundamentals
April 6, 2026 · The Yearfold team
Monte Carlo simulation for retirement, explained in 600 words
Why running 10,000 simulated retirements beats predicting one — explained without statistics jargon.
fundamentals · methodology
April 1, 2026 · The Yearfold team
How a realistic retirement calculator differs from the ones your bank offers
Most bank calculators ask three questions and assume a 7% return forever. Here's why that produces wildly optimistic numbers — and what to do about it.
fundamentals · methodology