Negative values in CA PPM show consistently between brackets and in red colour while positive values are displayed in black.
Resource Planning portlets like the resource Capacity portlet, do have TSV columns showing resource data like Capacity - Assignment.
The values for this field can be either positive or negative.
However, the Capacity portlets show negative fields between brackets, but in black colour. Why?
The reason why negative values across portlets shows in black and between brackets is due to the hyperlink of the cells.
The problem is that the TSV is also established as a link to another page and it is the link that is causing the colour to turn black. If you reconfigure the TSV to not be a link, it shows up as red just fine
This is common to all portlets on the system. The hyperlink colour is specified on the UI theme and is set to be displayed as black.
You can change that colour, but would change it to all hyperlinks regardless of the value behind. The colour does not distinguish the value contained. So if changed to red, all hyperlinks would display red.