This video explains how SPI is calculated, taking actual % complete and dividing it by planned % complete.
This is a measure of Schedule efficiency on a project. In other words, it is a ratio between what has been done and what should have been done by the current day. The calculation is Actual Project Percent Complete divided by Planned Project Percent Complete
What Does SPI Indicate?
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SPI = 1.0 → The project is on schedule
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SPI < 1.0 → The project is behind schedule
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SPI > 1.0 → The project is ahead of schedule
SPI provides a quick snapshot of schedule health and helps identify if corrective action is needed.
How is SPI Calculated?
SmartPM calculates SPI using the following formula:
SPI = Earned Duration ÷ Planned Duration
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Earned Duration: The amount of time your project should have taken to reach its current level of completion, based on the original schedule. Earned Duration measures it in time—showing how much planned schedule you’ve “earned” so far
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Planned Duration: The amount of time that should have been used by now according to the baseline schedule.
Example-
If your project has:
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Earned Duration = 60 days
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Planned Duration = 75 days
Then:
SPI = 60 ÷ 75 = 0.80
This means the project is operating at 80% schedule efficiency and is behind schedule.
Why is SPI Important?
SPI helps project teams:
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Monitor schedule health
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Identify risks early
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Make data-driven decisions to improve performance
By tracking SPI throughout the life of the project, you can ensure your team stays aligned and proactive.