How do I create a global bias negative region constraint?

A global bias negative region constraint acts as a magnet that can repel a group of nets and buses out of a region during global routing. The biased nets take priority in being pushed out of the bias region. This can result in the routing for the biased nets becoming more circuitous. Another way to conceptualize the negative bias region is as a soft blockage for a selected set of nets.
To create a global bias negative region:

Select a net, group of nets, or a bus from the Navigator assistant.
Click the Global Bias Setup icon on the Congestion Analysis assistant toolbar.
The Global Bias Setup form displays.
Click the New button to create a new global bias constraint group.
A group is created and assigned a name by default. The name can be a number in a series starting from GB00. Also, the net selected in the Navigator assistant appears in the Nets list box.
Add and remove nets in the Global Bias Setup form.
To edit the global bias constraint group name, click in the Global Bias text field and specify another name.
To add a negative bias region, click the + Rectangles button.
Click and drag to draw a region in the heat map. The region created on the heat map is used as the coordinates for the Bias Area.
The bias area is automatically assigned a name by default. The name can be a number in a series starting from vsrGlobalBias_AB_00 and is displayed in the Bias Areas list box.
Click the green ± symbol in the Bias column next to the bias area. This displays a red — symbol, which indicates a negative bias.
To see how the new constraint alters routing and congestion, click the ECO button in the Global Bias Setup form.
Alternatively, choose Global Route and ECO Congestion Analysis from the drop-down list.

How do I create a global bias negative region constraint?

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