---
title: "Stonqs blog: portfolio figures, privacy, how it works"
description: "Notes from building a portfolio tracker: how returns are calculated, what stays on your computer, and the decisions behind the app, with the figures to check."
url: "https://stonqs.app/blog/"
lang: "en"
updated: "2026-10-25"
---

# How the figures work, and what the app does with them

What each number on a portfolio screen actually measures, what leaves your computer, and why the app is built the way it is.

## Returns and figures

1. [ October 12, 2026 Your fee report says 5 EUR. Your portfolio paid 25.50.Buy 10 shares for 100 EUR with a 9.90 EUR commission, pay a 5.00 EUR account fee, and receive a 40 EUR dividend with 10.60 EUR withheld. Stonqs's charges report lists 5.00 EUR. The costs behind its cost rate are 25.50 EUR. Both are correct, because they answer different questions. 5 min read](https://stonqs.app/blog/portfolio-cost-two-figures/)
2. [ October 9, 2026 Your share rose 10 % and you still lost moneyA holding has a currency, the money that paid for it has a currency, and your report has a third. When they drift apart, part of your return is the exchange rate rather than the company. Here is that split, worked out, and where the rates behind it come from. 4 min read](https://stonqs.app/blog/currency-effect-in-a-portfolio/)
3. [ October 9, 2026 Why your two returns disagreeTime-weighted return measures the portfolio. Money-weighted return measures you. Put 10,000 EUR in before a good year and 40,000 EUR in before a bad one, and the same three years read as 5.9 % a year or 1.3 % a year, depending on which question you asked. 5 min read](https://stonqs.app/blog/time-weighted-vs-money-weighted-return/)

## Privacy and your data

1. [ October 9, 2026 What the AI assistant can and cannot doThe assistant has 70 tools. Three of them read nothing about your portfolio, 36 are reads that ask once and can be granted for a chat, and 31 write to your data and ask every single time, with no permission carrying over. Here is the whole model, including what it refuses to do. 5 min read](https://stonqs.app/blog/what-the-ai-assistant-can-and-cannot-do/)
2. [ October 9, 2026 What the profile password protects, and what it does notStonqs keeps your portfolio in one file on your own disk. Give the profile a password and that file is encrypted with SQLCipher under a random 256-bit key, which your password only ever unlocks. That stops a stolen laptop and a copied backup. It does not stop four other things. 5 min read](https://stonqs.app/blog/how-the-profile-password-encrypts-your-portfolio/)

## Inside the app

1. [ October 9, 2026 What broker CSV exports actually containWe read 29 export layouts from 26 brokers without being told which column is which. They agree on almost nothing: nine ways of writing a date, two decimal separators, and an identifier for the instrument in only 13 of them. This is the whole table, and what each disagreement costs. 6 min read](https://stonqs.app/blog/what-broker-csv-exports-contain/)

---

[ Stonqs](https://stonqs.app/)

A portfolio tracker that runs on your own computer. Free, open source, no account.

## Product

[Download](https://stonqs.app/download/) [Privacy](https://stonqs.app/privacy/)

## Learn

[Guides](https://stonqs.app/guides/) [Blog](https://stonqs.app/blog/) [FAQ](https://stonqs.app/faq/)

## Project

[About](https://stonqs.app/about/) [Source code](https://github.com/vvvlladimir/stonqs) [Changelog](https://github.com/vvvlladimir/stonqs/blob/main/CHANGELOG.md) [Discussions](https://github.com/vvvlladimir/stonqs/discussions) [Report a bug](https://github.com/vvvlladimir/stonqs/issues)

Stonqs is a tool for recording and analysing your own investments. It is not financial, tax or legal advice, and neither are the answers of its assistant. Market data comes from free third-party sources with no guarantee of accuracy. This site sets no cookies and loads nothing from other servers; the only thing it keeps in your browser is the language you pick.

[Legal notice](https://stonqs.app/legal-notice/) [Privacy policy](https://stonqs.app/privacy-policy/)