This example demonstrates a JavaScript utility for tracking and reporting progress as a percentage of a total item count. It monitors progress changes and triggers callbacks when significant increments occur, passing the current percentage and elapsed time between updates. The implementation uses `Date.now()` through a custom `msNow()` helper to measure timing, with functions like `createProgress` and `report` managing state. It relies on plain JavaScript object methods and callbacks, with no external visualization libraries, making it suitable for command-line or server-side progress reporting.