Sometimes you can have a lot of investments in your portfolio with a negative result, while you have a positive score in the Battle. This happens because we measure the result of your positions during the Battle itself.
Let's explain this with an example:
Say, a while ago you bought some stocks in Facebook, which was at that time worth 60.50. The value of your position however decreased to 51.30 when the Battle started. During the Battle, the price of a Facebook stock increased again to 56.40. In your portfolio overview there is still a negative result, but during the Battle, you have a positive result in this position and therefore a positive score.