I don't think you understand PTS. Here's an explainer I posted earlier: https://bitcointalksearch.org/topic/m.10012941
The rise and fall of PTS correlates around moments in time known as "snapshots". Pre snapshot, PTS value goes up; post snapshot, PTS value drops. This is because a snapshot gives you stake in a new DAC project, so by holding the PTS in your wallet at that moment you gain a stake in the project that the snapshot was taken for. After people get their stake, some tend to dump while others would take that opportunity to buy low for the next snapshot.