skills/crunchbase-market-mapper/references/calculation-spec.md

# Calculation Specification

Use these definitions for recency, market, and monitoring metrics. The optional `scripts/derive_metrics.py` helper implements the same rules.

## General rules

- Fix one `as_of` date at the start of the task in the user's timezone.
- Deduplicate organizations and rounds by UUID before calculating.
- Use `value_usd` for money calculations.
- Exclude `—` amounts from sums, medians, and concentration calculations; count those rounds separately.
- Reject future event dates from calculations and surface them for review.
- Keep raw retrieved values separate from derived labels.

## Full months since an event

For event date `E` and as-of date `D`:

`months = ((D.year - E.year) * 12 + (D.month - E.month)) - (1 if D.day < E.day else 0)`

Do not divide elapsed days by 30.

Funding-recency labels:

- Fewer than 12 full months: `recent`
- 12 through 17 full months: `intermediate`
- 18 or more full months: `extended interval`
- No returned event date: `—`

These labels describe timing only. They do not establish fundraising intent, company health, or outreach priority.

## Trailing capital windows

Using calendar-month subtraction:

- Current period: `[D minus 12 months, D]`
- Prior period: `[D minus 24 months, D minus 12 months)`

For each period report:

- Total round count
- Rounds with a numeric USD amount
- Rounds shown as `—`
- Total disclosed USD capital
- Median numeric round size
- Funding-type mix by count

When the prior value is zero, show percent change as `n/a` rather than dividing by zero.

## Concentration

Calculate top-three concentration over the trailing 24-month window as the sum of the three largest numeric round amounts divided by total numeric capital in that window. Report `n/a` when total numeric capital is zero.

## Formation

Bucket confirmed organizations by the year component of `founded_on`. Label the result “formation within the confirmed universe.” Do not extrapolate it to the whole market.