> For the complete documentation index, see [llms.txt](https://docs.tradesurge.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tradesurge.co/concepts-and-reference/r-and-expectancy.md).
# R and expectancy
TradeSurge measures everything in R. Expectancy in R is the only profitability number.
R is the amount you risk on one trade. TradeSurge measures every result in R, so accounts of different sizes at different firms can be compared on one scale. Expectancy in R is the one number that says whether a strategy makes money.
## What 1R is
1R is what you lose if your stop is hit. If you risk 0.5% of a 100k account, 1R is 0.5% of that account. A trade that makes twice the risk is a +2R trade. A trade stopped out in full is a -1R trade.
## Expectancy is the only profitability number
Expectancy is what you make per trade, on average, in R.
`Expectancy = Win% × average win - Loss% × average loss`
A strategy that wins 40% of the time with 2R winners and 1R losers has an expectancy of 0.4 × 2 - 0.6 × 1 = +0.2R per trade. Positive expectancy means the strategy makes money over enough trades.
## Why not win rate or dollars
| Name | What it means |
| ------------ | ------------------------------------------------------------------------------ |
| **Win rate** | Hides the size of wins and losses. A high win rate can still lose money. |
| **Dollars** | Change with account size and risk setting, so two accounts cannot be compared. |
| **R** | Normalises every trade to what was risked, on every account. |
TradeSurge never ranks, scores or judges you on win rate or dollars.
## Where R shows up
* The Terminal sizes every order from your risk dial, so 1R means the same thing on every account.
* The Dashboard, Journal and Surge score report results in R.
* Backtests and the simulator report expectancy in R.
{% hint style="info" %}
Scaling one edge across more accounts only works if the edge is positive in R. Copying a negative-expectancy strategy to ten accounts loses ten times as fast.
{% endhint %}
## Next steps
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.
Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:
```
GET https://docs.tradesurge.co/concepts-and-reference/r-and-expectancy.md?ask=&goal=
```
`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.