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Once you’ve completed a sprint or two, you can use the velocity chart to forecast how much of your backlog you’ll finish each sprint.
Forecast your upcoming sprint
From the backlog page, open the velocity chart.
.png "Click the the velocity chart in the upper right")
In the chart, you can see how many story points (or whatever you use to estimate your backlog) your team has completed in the previous sprints.
.png "Velocity chart showing 32 and 30 points completed")
Go back to the backlog page, turn forecasting on, and enter your predicted velocity.
.png "Changing velocity changes forecast lines")
Forecast lines show how much work your team should be able to complete in future sprints.