Data Sources & Methodology
MarketWall turns raw market and filing data into a live, filterable feed of technical and fundamental signals. This page explains where that data comes from, how each signal is actually calculated, and how often it updates — so you can judge the numbers on this site the same way you’d judge any other source.
Data sources
Price & volume history
Daily OHLCV history for every tracked stock, crypto, and commodity future comes from Yahoo Finance market data, refreshed continuously. Alpaca's IEX exchange feed adds a faster, ~60-second refresh on top of that for stocks currently showing an active signal, so today's still-forming bar doesn't lag behind the market by the full sweep interval.
Insider transactions
Insider buy/sell activity (Form 4 filings) is read directly from SEC EDGAR, not a third-party summary — including each filer's SEC CIK, so the same person's transactions across different companies are correctly linked to one profile.
Revenue history
Quarterly revenue, used by the Revenue-Price Divergence signal and the revenue-growth chart overlay, comes from SEC EDGAR's structured XBRL company-facts data — typically 9-10 years of quarterly history for large caps, sourced straight from the filings themselves rather than a restated summary.
Institutional ownership
Quarter-over-quarter institutional holdings are aggregated from SEC 13F bulk filing data — every institutional manager's disclosed holdings, reduced down to a per-symbol view.
Fundamentals & analyst data
Valuation ratios, analyst price targets, and next-earnings dates are sourced from Yahoo Finance and Finnhub and refreshed weekly — this data doesn't move fast enough to need a faster cadence.
How signals are calculated
A background engine re-scores every tracked symbol against each filter below on a continuous loop — roughly every 3 minutes for price/volume-based signals — and writes whatever currently qualifies to the live feed. Nothing on the dashboard, discover screen, or these glossary pages is computed in the browser; the site only ever displays what this engine most recently wrote.
200 SMA Touch
How close a symbol's current price is sitting to its 200-day simple moving average — a level a lot of longer-term technical analysis treats as a dividing line between an uptrend and a downtrend.
Volume Spike
Today's trading volume compared against the trailing 20-session average. A sudden, well-above-average volume day often means something changed — news, an institutional order, a shift in sentiment — even before the price itself has fully reacted.
Support Confirmation / Reject
MarketWall finds a symbol's most-revisited price zone over its own trailing trading history, then flags the moment price reacts to it — holding above it (confirmation) or breaking below it (reject).
Bollinger Breakout / Breakdown
A move outside the symbol's own 20-day Bollinger Bands (2 standard deviations from a 20-day moving average) — a band that widens for volatile names and tightens for quiet ones automatically, so the same rule applies fairly across very different symbols.
RSI Divergence
When price makes a new high or low but the 14-period Relative Strength Index doesn't confirm it — a classic early-warning pattern that momentum may be fading before price itself turns.
Plateau
Names that fell meaningfully off a recent peak, then stopped falling and have been trading in a tight, flat range since — a base that may or may not hold, surfaced for a closer look rather than as a prediction either way.
Revenue-Price Divergence
A fundamentals-vs-price check, not a chart pattern: quarterly revenue (from SEC filings) growing year-over-year while the stock price has been sliding over the same span. Stock-only — it depends on SEC filing history, which crypto and commodities don't have.
Update frequency
- Technical signals (SMA, volume, support/resistance, Bollinger, RSI, plateau): recalculated on a continuous ~3-minute loop.
- Stock prices: refreshed continuously, with a faster ~60-second layer for symbols currently showing a signal.
- Insider transactions (Form 4) and revenue history: synced weekly from SEC EDGAR.
- Institutional ownership (13F): synced quarterly, matching the SEC’s own filing cadence.
- Fundamentals and analyst data: refreshed weekly.
Not investment advice. Everything on this page and across MarketWall — scores, signals, and rankings included — describes what the data currently shows, not a recommendation to buy or sell anything. Make your own decisions based on your own research.
See the signals described above running against real symbols in the interactive walkthrough, or look them up individually in the glossary.