PCI is zero for LTE cells

I was able to find a reply on this topic from a couple of years ago (PCI for LTE and PSC for UMTS), but I wanted to know if this is the same issue and if anything has changed since then. I downloaded csv data for Singapore using the https://opencellid.org/downloads.php site. When I look at any of the LTE data that is located in area 505 (the Tracking Area Code), the unit column or PCI (Physical Cell Id) is all zeros or negative ones. I’m assuming that this means that the PCI is not available, correct?