Building tiedown negative value

[Henry94606]

In calculate shearwall I had a long SW that resulted in tiedown value as negative.
How should I understand this in layman terms ?
After reduce the length of the SW, I had it a positive number. Wonder if at certain lengths, SW starts to yield negative tiedown value.

 

[Celt83]

For any calculation step 1: establish a sign convention, this will allow you to differentiate tension and compression so you can understand physically what signed numbers indicate.

 

[TRAK.Structural]

The aspect ratio, gravity loads, and the lateral force will determine the net uplift at the tension side of a shear wall. It is certainly possible for a shear wall to have no net uplift reaction.