Site-wide methodology · Updated May 8, 2026
Methodology & Data Sources
Every number on CompoundLadder traces back to a public, US-government or peer-reviewed source. This page is the single place to see which dataset powers which calculator, when each source refreshes, what we assume when we interpolate, and where our outputs stop being reliable. If you spot an error, the corrections policy is below.
By Yi Liu · Updated May 8, 2026
At-a-glance data sources
Seven primary datasets feed the site. Each row lists the release vintage we are currently citing, the pages that depend on it, and the next expected refresh.
| Dataset | Vintage | Used in | Next release |
|---|---|---|---|
| Federal Reserve SCF 2022 | Released Sept 2023 | All net-worth percentile pages, age/income joint tables | Fall 2026 (SCF 2025 expected) |
| Census ACS 5-year 2023 | Released Dec 2024 | 50 state middle-class pages, city income percentile pages | Dec 2026 |
| Census ACS 1-year 2024 | Released Sept 2025 | Top-10 city income pages | Sept 2026 |
| BLS CPI | Monthly | Inflation adjustments in FIRE/SWR calculators | Monthly |
| SSA POMS + Trustees Report | Annual (April) | Social Security break-even, 2033 projections | April 2026 |
| IRS Pub 590-A / 590-B | Annual | IRA / 401(k) / HSA contribution limits, RMD tables | January 2026 |
| CMS / HealthCare.gov | Annual | Pre-Medicare gap ACA subsidies | November 2025 |
How we use each source
Federal Reserve SCF (Survey of Consumer Finances)
We use the public-use extract — not the full PUF (Public Use File) — to build household-level percentile tables by age bracket and income bracket. Joint percentiles (e.g., "net worth at age 35–44 with $75k–$100k income") are interpolated where the SCF's released tables have thin cells (typically n < 30). The SCF is the gold standard for US wealth distribution but is released triennially, so the 2022 wave remains the most recent through fall 2026.
Census ACS (American Community Survey)
State and metro income percentiles come from ACS. We prefer the 5-year aggregate (2019–2023) for smaller geographies — every state page and the long tail of city pages — because the larger sample tightens confidence intervals at the extremes (10th, 90th, 95th percentile). For the top-10 metros where sample size is adequate, we use the more recent 1-year 2024 file. We surface the vintage on each page so readers can match it to other sources they may be comparing against.
BLS CPI (Consumer Price Index)
Real-dollar conversions in compounding and FIRE calculators use CPI-U (all-urban consumers), not chain-weighted CPI. The seasonally-unadjusted series is fetched monthly. For long-horizon back-tests we use annual averages.
SSA (Social Security Administration)
The PIA (Primary Insurance Amount) formula, bend points, the early-claiming reduction schedule, the delayed-retirement credit, and Trustees Report long-run projections (the well-known 2033 trust-fund depletion estimate) all come from SSA POMS and the annual Trustees Report. We re-pull the bend points and COLA each January.
IRS publications
Annual contribution limits (IRA, 401(k), HSA, FSA), catch-up thresholds for age 50+ and the new SECURE 2.0 age-60–63 super-catch-up, and the Uniform Lifetime Table for RMDs come from Pub 590-A, Pub 590-B, and Notice releases. These typically refresh in late October (limits) and the IRS confirms by January.
CMS / HealthCare.gov
Federal Poverty Level (FPL), ACA Premium Tax Credit phase-outs, and the status of the 400% FPL subsidy cliff (currently softened through 2025 by the Inflation Reduction Act, scheduled to revert) drive the pre-Medicare gap calculator. We re-check this in November each year ahead of open enrollment.
Update cadence
We commit to the following refresh discipline so readers know how stale (or fresh) any given page is.
- Major data refreshWithin 30 days of source release. New SCF wave, new ACS vintage, new IRS limits, new SSA bend points all trigger same-month rebuilds of every dependent page.
- Calculator accuracy reviewQuarterly. We re-run a regression of each calculator against hand-computed reference cases to catch drift after dependency upgrades.
- SEO vintage tagsAnnually(every January). We update titles, descriptions, and on-page year stamps (e.g., "2026" → "2027") once we are confident the underlying data still applies for the new year.
- Author time commitment~5 hours per week minimum. CompoundLadder is a side project run by one person; this is the floor that keeps the site updated and the inbox cleared, not an upper bound.
Known limitations
Every dataset has edges. These are the ones we run into most and the simplifications they force on us.
- Single-year age cells are interpolated.The SCF publishes 10-year age brackets (under-35, 35–44, 45–54, 55–64, 65–74, 75+). When a page says "net worth at 35," we are interpolating linearly within the 35–44 bracket — we do not have true single-year resolution.
- Net-worth definition. We follow the SCF definition: assets minus liabilities, including primary-residence equity (home value minus mortgage balance). Some sources exclude primary residence; others include employer-DB pension wealth. Comparisons across sources can drift 10–20% from this difference alone.
- US-only coverage. All figures are United States. We do not cover UK / EU / Canada / Australia distributions, taxes, or retirement accounts beyond the lightly-touched ISA/SIPP examples.
- Federal tax only. Tax calculations assume federal brackets. State income tax, local tax, and FICA-related caps are excluded unless explicitly noted. For state-tax-sensitive decisions (Roth conversions, RMD timing) consult a qualified preparer.
- Educational, not advisory. Every output is a benchmark or a scenario, never a personalized recommendation. CompoundLadder does not, and cannot legally, provide individualized financial advice.
Author & credentials
AI engineer working on large language model systems by day; long-time personal-finance hobbyist tracking my own net worth in spreadsheets since my early twenties. CompoundLadder is where I combine those two worlds — rigorous engineering meets honest, tool-centric personal-finance education. Full background on the about page.
Important disclosures: I am not a Certified Financial Planner (CFP), not a Financial Adviser (FA), and not a licensed investment adviser. CompoundLadder publishes educational benchmarks and free calculators only. Nothing on this site is personalized financial, tax, or legal advice.
Corrections policy
If you find a factual error, a broken formula, an outdated vintage, or a missing caveat, write to lyccol3@gmail.com with the URL and the specific issue. We reply within 7 days, usually faster.
- Substantive errors (wrong number, wrong formula, wrong citation) are corrected in place and logged below with a dated entry.
- Typos and small clarifications are fixed silently without a changelog entry.
- Vintage updates (e.g., new SCF wave, new ACS release) are rolled out site-wide and appear in the changelog as a single entry referencing all affected pages.
Changelog
Reverse-chronological, last several material changes. Minor typo fixes are omitted.
- 2026-05-08Added /am-i-behind-at-55 page; Wave 3 visual polish rolled out across 12 existing pages (gradient headers, hover-lift cards, tabular-nums tables).
- 2026-05-07Created Wave 2 content: the anxiety-Q series ("am I behind at 25/30/35/40/45/50"), long-form guide pages, and the Social Security break-even calculator page.
- 2026-05-03R37 — canonical domain unified to
www.compoundladder.comfor Google Search Console coverage. All internal absolute links and the GSC property re-pointed to match. - 2026-04-28R34 — calibrated 50-state ACS middle-class income data vintage to the December 2024 release (ACS 5-year 2019–2023). Prior vintage was 2022. All 50 state pages rebuilt.
- 2026-04-20R33 — CTR optimization sweep. Rewrote every SERP-facing title tag and meta description using the emotional-trigger + data-point pattern across ~100 pages.
- 2026-04-15Launched city income percentile pages for the top 10 US metros, using ACS 1-year 2024 data.
- 2026-04-01Initial launch — 33 calculators plus 80-spoke net-worth-percentile hub built from SCF 2022.