Methodology and data sources
Last updated: (Istanbul) · latest data day 19 Oct 2026
This page explains where StockFortuna's numbers come from, how often they are refreshed and how they are calculated. The formulas match the calculation in the site's source code; if a calculation changes, this page changes too.
Who prepares it?
StockFortuna is an independent market data website. Calculations and pages are generated automatically by software written by the StockFortuna team; Taner Çoban is responsible for the content and publication (Muratpaşa / Antalya, Türkiye). Contact: [email protected] · About · Contact form.
Data sources and update frequency
| Data | Source | Delay / frequency |
|---|---|---|
| Stock prices (open, high, low, close, volume) | yfinance (Yahoo Finance data), daily bars, 2-year history | End of day, delayed; analysis pages are regenerated every trading day after 19:00 (Istanbul) |
| BIST 100 universe and company names | The site's symbol list (tickers.py); company names from the KAP list | Updated when the universe changes |
| Sector / industry label | yfinance company info (sector, industry) | Refreshed every 10 days; if the source is empty, no sector section is shown |
| Dividends and next earnings date | yfinance dividend history and company calendar | From a 24-hour cache; section hidden if there is no record |
| KAP disclosures | The public disclosure list of the Public Disclosure Platform (kap.org.tr) | Periodically in the background |
| Investment funds | TEFAS public fund data (tefas.gov.tr) | End of day; fund pages every 6 hours |
| Gold, silver, FX, Brent | yfinance (e.g. COMEX gold futures GC=F, USD/TRY); gram gold = ounce × USD/TRY ÷ 31.1034768 | Pages refreshed hourly |
| Economic calendar | Official sources and publication rules (Fed FOMC calendar, TurkStat CPI rule, CMB reporting deadlines); CBRT MPC dates entered by hand from the announcement | When the calendar changes |
How the indicators are calculated
All measures on the stock analysis pages are recomputed from the same end-of-day closing series when the page is generated. What each indicator means and how it looks on a chart is explained in the pattern and indicator glossary.
| Measure | How it is calculated |
|---|---|
| Trend | Close > 50-day average > 200-day average is an uptrend; close < SMA50 < SMA200 a downtrend; anything else balanced / undecided. A description of state, not a signal. |
| Relative strength (RS) | Percentile rank (0–100) of the last 126 trading days' return (ROC126) within the BIST 100 universe. 80 means the stock returned more than 80% of the universe. |
| Returns | Percent change of the last close versus the close 1, 5, 21, 63 and 252 trading days earlier. |
| 52-week range and position | Highest and lowest of the last 252 closes; position = (close − low) ÷ (high − low) × 100. |
| Monthly closes | Close of the last trading day of each month and the change versus the previous month-end; the current month is marked "month to date". |
| Volatility | Standard deviation of daily returns × √252 (annualised), for the last 20 trading days and the last year. |
| Volume ratio | Average volume of the last 20 days ÷ average volume of the last 252 days. |
| SMA / EMA 5·10·20·50·100·200 | Simple average of the last n closes; exponential average weighted with α = 2 ÷ (n + 1). |
| RSI (14) | Wilder method: average gain and loss smoothed with α = 1/14; RSI = 100 − 100 ÷ (1 + gain/loss). |
| MACD (12,26) | Difference of the 12- and 26-day exponential averages (signal line on charts: 9-day EMA). |
| Stochastic (9,6) and Stochastic RSI (14) | %K: where the close sits in the last 9 days' low–high range, averaged over 6 days; Stochastic RSI: where RSI sits in its last 14 values' range. |
| ADX / DI (14) | Directional movement (DI+, DI−) relative to average true range; ADX is the Wilder-smoothed average of the DI spread. |
| Williams %R (14) · CCI (14) · Ultimate Osc (7/14/28) · ROC (12) · Bull/Bear Power (13) | Standard definitions with the parameters in brackets. Bull/Bear Power: distance of the high and low from the 13-day EMA. |
| 1-2-3 neckline breakout | On 5% ZigZag turning points, a low (1) → high (2) → higher low (3) structure; "detected" is shown when a close crosses the high (2) level within the last 3 trading days. |
| Sector comparison | The same measures for BIST 100 stocks in the same yfinance sector, side by side (alphabetical), plus the median 1-year change. No ranking or selection is made. |
Limitations
- Prices come from third-party sources with a delay; they may be incomplete, wrong or corrected later. Split and bonus-issue adjustments are only as good as the source's.
- Sector labels are the yfinance classification and may differ from the official KAP or Borsa Istanbul sector classification.
- Indicators are computed from past prices; past behaviour does not show future prices. Automatic pattern detection is rule-based and may differ from what a human eye sees.
- The pages cover only the BIST 100 universe; other stocks can be studied in the interactive app.
Not investment advice
StockFortuna does not recommend stocks; it gives no buy/sell guidance, price targets, stop levels or score rankings. Everything on the site is a presentation of measured data for information only. Under Turkish Capital Markets Law No. 6362 investment advice may only be given by licensed institutions. This English text is a convenience translation; the Turkish version is binding. Legal text: Data and method · Not investment advice · Risk disclosure.
For your own research
BIST 100 stock analyses · My Screener (you choose the conditions) · Screening Wizard · Chart Studio · Glossary