How is "movement" measured?

As the absolute number of calendar days between the baseline deadline and each scenario's resulting deadline, regardless of which direction the change moves it.

Why might a smaller duration change move the deadline more than a larger one?

Because business-day mode only counts weekends and exclusions, so a small change that happens to cross an extra weekend can move the final calendar date further than a larger change that does not.

Deadline Sensitivity Calculator

Name up to three scenarios, each changing the duration by a chosen number of days, and see which one actually moves the deadline the most.

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Why Deadline Buffers Need to Be Sized, Not Guessed

Worked example

From a Monday start with a 3-business-day baseline, a "plus 1 day duration" scenario moves the deadline by 1 calendar day, while a "plus 3 day duration" scenario moves it by 5 calendar days, since the larger change happens to cross an extra weekend along the way. That larger duration change turns out to be the more sensitive driver here and ranks first, but a differently timed 1-day change that itself crossed a weekend could just as easily outrank a 3-day change that did not.

Common mistakes

Assuming movement scales linearly with the size of the input change. Crossing a weekend or an exclusion can make a small change move the deadline more than a larger one that does not cross one.
Treating the ranking as a measure of how likely each scenario is to happen. It only measures how much the deadline moves, not the probability of any scenario occurring.

Limitations

Only duration is perturbed across these scenarios. This does not model probability or likelihood of any scenario actually happening, only the mechanical effect on the resulting deadline.

Frequently asked questions

How is "movement" measured?: As the absolute number of calendar days between the baseline deadline and each scenario's resulting deadline, regardless of which direction the change moves it.
Why might a smaller duration change move the deadline more than a larger one?: Because business-day mode only counts weekends and exclusions, so a small change that happens to cross an extra weekend can move the final calendar date further than a larger change that does not.