Reference

How to cite

The metric is free to use, adopt, and reference. The original definition appears in The Delivery Gap; this site is the canonical online definition.

In writing

For papers, posts, and reports, the simplest reference is:

Hill, B. (2026). The Delivery Gap. See costperacceptedchange.org for the canonical definition.

BibTeX

@book{hill2026deliverygap,
  author    = {Hill, Brenn},
  title     = {The Delivery Gap},
  year      = {2026},
}

@misc{cpac2026,
  author       = {Hill, Brenn},
  title        = {Cost per accepted change: canonical definition},
  year         = {2026},
  howpublished = {\url{https://costperacceptedchange.org}},
}

Plain text

Cost per accepted change, defined in Hill (2026), The Delivery Gap.
Canonical reference: https://costperacceptedchange.org

Inline first mention

The recommended phrasing for the first mention of the metric in any document is:

cost per accepted change — the fully-loaded cost of producing software that reaches production and stays there, divided by the number of changes that do (Hill, 2026).

In dashboards and tooling

When the metric is exposed in a dashboard, report it alongside the formula and the window length. The minimum recommended label is:

Cost per accepted change — last 4 weeks
$ per change that reached production and stayed there
Source: https://costperacceptedchange.org

Naming convention

The metric is written as cost per accepted change — lowercase, no acronym, no hyphenation. The acronym CPAC is in informal use but conflicts with a major political brand and is discouraged in canonical materials.

License

The definition is free to use. The calculator library is MIT-licensed: github.com/brennhill/cost-per-accepted-change.