# What's the difference between a metric and a modeled metric?

## Programmatic and Organizational Metric

A **metric** is a value that someone **enters or reports directly** for a record (or pact)—it’s *declared*, not calculated.

* **Source:** human-reported (manual entry or spreadsheet import)
* **Examples:** “Acres treated,” “Linear feet restored,” “Number of trees planted,” “Number of Volunteers”
* **What it represents:** what was *done* and how it relates to broader goals.
* **Where it lives:** attached to an **activity record** and/or **pact**, often tied to an activity type and/or a funder program metric list

Programmatic metric lists are defined by a funding program and available to users to select once a pact within the program has been created.

Organizational metrics are available to standard users who want to curate their own list of metrics and assign them to activity records. 

## Modeled metric

A **modeled metric** is a value that FieldDoc computes by running a model with user provided inputs such as activity type, geometry/footprint, extent, context layers, etc. . It’s *derived*.

* **Source:** model output (calculated)
* **Examples:** “Estimated nitrogen reduction,” “Estimated phosphorus reduction,” “Sediment reduction,” “Estimated runoff reduction,” sometimes “Estimated GHG benefit,” etc.
* **What it represents:** the *estimated impact* of what was done, based on an accepted methodology
* **Where it comes from:** the **Model Library / model run.** A model run and the resulting modeled metrics can bet assigned to a pact or an individual activity record. 

#### Practical rule of thumb

* If you can answer **“Where did this number come from?”** with *“Someone reported it”,* that's a **metric**
* If the answer is *“The model calculated it from inputs/geometry”,* that's a  **modeled metric**

#### Why it matters

* **Metrics** are great for tracking *scope and delivery* (what, where, how much).
* **Modeled metrics** are what you use for *defensible impact reporting* when a program needs standardized estimates across projects.