About Sun Insight Lab
Sun Insight Lab is an independent educational project at suninsightlab.com. It pairs a browser-based historical investment simulator with plain-English writing on risk, valuation, diversification, and time horizon. It's built for everyday investors who want to test ideas against real historical data — and understand the reasoning — before committing capital.
What you'll find here
| Section | What it does |
|---|---|
| Quant Lab | Backtest rule-based factor strategies — market cap, momentum, low volatility, value, and quality — across the whole S&P 500. |
| Simulator | Three modes — Single, Compare, and Portfolio (weighted, with optional monthly rebalancing) — over historical monthly data. |
| Retirement | Backtest a TSP or 401(k) payroll-contribution plan against an S&P 500 benchmark. |
| AI Bubble Meter | A breadth-and-concentration gauge for how narrow the current market rally has become. |
| Analysis | Market notes across four tracks: Market Trend, Deep Dives, Breaking, and Basics. |
| Resources | A library of guides organized by level: Beginner, Intermediate, and Advanced (including options strategies). |
Our mission
Make investment decision-making more disciplined. We prioritize clarity over hype and encourage readers to weigh downside risk, time horizon, and personal constraints before allocating capital. Every claim on the site is either derived from public price data or from documented assumptions stated in plain text.
How the simulator is built
The simulator is a Web Component written in vanilla JavaScript. It fetches monthly closing-price data (sourced from Yahoo Finance) from our database over a small read-only JSON API, runs a deterministic month-by-month allocation across your selected period, and draws the result with Chart.js. The whole calculation runs in your browser, so you can read the source and reproduce every number.
- Coverage: US-listed stocks, ETFs, the S&P 500, and Bitcoin, from 2010 to the most recent monthly close.
- Update cadence: monthly closes refreshed after each month ends; market news refreshed daily.
- Reproducibility: the price API is public and read-only; script tags use
?v=cache-busters whenever the logic changes.
Who's behind it
Sun Insight Lab is an independent, one-person project — founded, written, edited, and maintained by a single long-term individual investor, not a media company or a financial firm. It began with the simulator, built to answer one recurring question from friends and family: "what would have happened if I'd invested X every month into Y for Z years?" Answering that honestly meant building a tool that used real prices and showed its work. The structured library of articles grew out of the same instinct — readers kept needing the why behind the numbers.
The perspective here is deliberately that of a patient, evidence-first individual investor: more interested in how decisions compound over years than in next week's price. Sun Insight Lab is not a licensed investment adviser, broker, or fund manager; it earns nothing from the assets it discusses, runs no affiliate links to brokerages, and offers no personalized advice. The only thing it asks of you is your attention.
How content is made
Every article starts from primary sources — company filings, the historical price record, and figures we can reproduce in the simulator — rather than from other blogs or rewritten press releases. Quantitative claims are checked against the same public price API the tools run on, so anything we publish about a stock or a strategy can be re-run and verified by a reader. Where a post discusses a specific period, we tie it to a simulator scenario you can replay yourself.
We use AI tools to help draft and illustrate some content, but nothing is published on autopilot. A human reviews every piece for accuracy, rewrites it into plain English, removes anything that can't be supported, and is accountable for what goes live. We disclose this plainly because it is how the work is actually done — the full process, including how we handle corrections, is in our editorial policy. When we get something wrong, we fix it and say so.
Reach us at [email protected] or via the contact page.
What this site is not
We do not provide personalized financial advice, brokerage services, portfolio management, or guaranteed-return claims. The simulator does not model taxes, dividends, trading fees, slippage, bid/ask spreads, or account-specific rules — real-world results will differ. See our Disclaimer.
How to verify our work
- Reproduce a simulation: open the homepage, pick the same asset and date range used in any article, and confirm the totals match.
- Inspect the data: the price API at
/api/prices?symbols=returns the same monthly closes the simulator uses. - Read the source: the simulator file
stock-calculator.jsis unminified. - Report a discrepancy: use the contact page with the URL, the parameters, and your cross-check source.