Monte Carlo Forecast "When" Chart

When will these items be done, and how likely is that?

A table with 19 rows, from 95% down to 5%. Each row reads: in this share of 10,000 simulated futures, all currently open work items were finished by this date ("Target date"), after this many periods ("Iterations").

Two sources

"Throughput source" provides the history: how many work items were resolved per period. "Open items source" provides the work to forecast: its unresolved work items. Both can be the same project or saved filter, or different ones.

How the forecast is calculated

The history is the number of work items resolved in each complete period (day, week or month) of the window; the current period is left out. The header line shows what it was based on, for example "Based on 12 complete weeks since 2026-08-03 · 10,000 simulations".

The work to forecast is Jira's count of the unresolved work items in the open items source, for example "≈ 42 open work items". Jira's count is approximate, and the forecast keeps it fixed. The header says so: "The number of open work items is Jira's approximate count and stays fixed: work items added later are not forecast." Why the count is approximate is explained under Approximate counts.

Each simulation starts today. It moves forward one period at a time and subtracts one past period's number, drawn at random, until no open work items remain. So the earliest possible date is one period from today. The rows then sort the 10,000 finish dates: the 85% row shows the date by which 85% of the simulations had finished. See Monte Carlo forecasts.

A simulation that has not finished after 10 years is stopped and counts as not finished. A row that falls among those shows "not within 10 years", and a line above the table says how many there were: "… of 10,000 simulations (…%) did not clear the backlog within 10 years." A target date on a Saturday or Sunday is shown in gray.

Settings

There is no forecast horizon to set; the forecast runs until the work is done or 10 years have passed.

When there is no forecast

• If Jira's count cannot be read: "Jira's count of open work items could not be read, and the forecast needs it."
• If the open items source has nothing open: "The open items source has no unresolved work items, so there is nothing to forecast."
• If nothing was resolved in the history: "No work items were resolved in the throughput window, so there is no history to forecast from."

Opening work items

The line "Sample: … resolved in that window (click to open)" opens the resolved work items the history is based on, up to 300. The "open work items" figure opens the open work items in Jira's search, with no limit.