> For the complete documentation index, see [llms.txt](https://docs.score-environnemental.be/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.score-environnemental.be/eng/methodology/produit/production-system/origine.md).
# Environmental policy
The evaluation of environmental policies is referred to hereafter as the "origin score". Its aim is to reflect the producer country's environmental policy (discharge standards, electricity production, biodiversity, etc.). It is based on the work of the Environmental Performance Index (EPI).
## 
Environnemental Performance Index
The EPI is an index created by researchers at Yale University and Columbia to determine the performance of each country's environmental policies and its impact on the environment.
An update is published every two years on the site:[ https://epi.yale.edu/](https://epi.yale.edu/)
It brings together 180 countries and aggregates 32 performance indicators grouped into 11 categories:
1. Air quality
2. Water quality
3. Heavy metals
4. Waste management
5. Biodiversity & habitat
6. Ecosystem management
7. Peach
8. Climate change
9. Pollutant emissions
10. Agriculture
11. Water resources
## Standardization
The original score (out of 100) is normalized on a scale of 0 to 100 with:
* 100 → the highest rated country's EPI
* 0 → the world average of EPI
This means for example that:
* The country with the best EPI (Denmark) has a score of 100/100
* A country that has EPI less than or equal to the world average at a score of 0/100
The normalization formula is as follows:
$$
score = \frac{x-\overline{epi}}{epi\_a -\overline{epi}}\*100
$$
> * $$x$$ is the EPI of the concerned country
> * $$\overline{epi}$$ is the world average of EPI (46.6 in 2020)
> * $$epi\_a$$ is the country with the best score (Denmark - 82.5 in 2020)
{% hint style="info" %}
The score is bounded in the interval \[0, 100]
{% endhint %}
## Scores by country
The original scores calculated using the above methodology are available here :
{% content-ref url="/pages/-MDte5QeJNbMykPtwTdm" %}
[Country score](/eng/methodology/produit/production-system/origine/synthese.md)
{% endcontent-ref %}
## Score calculation
The following formula makes it possible to obtain the origin score on 100 points, taking into account $$n$$ ingredients involved in a recipe:
$$
score = \sum\_{i=1}^{n}a\_i\*p\_i
$$
> $$n$$ the number of ingredients\
> $$a\_i$$ the origin score associated with the country\
> $$p\_i$$ the percentage of the ingredient present in the recipe
{% hint style="info" %}
The sum of the percentages is always equal to 100: $$\sum\_{i=1}^{n}p\_i = 100$$
{% endhint %}
The original score is integrated into the overall score of the product in the form of a bonus / penalty: between -5 and +5 points. The original bonus / penalty is calculated as follows:
$$
bonus = \frac{x}{10}-5
$$
> $$x$$ corresponds to the original score
## Sources
{% embed url="" %}