Is it normal to get zero as the value for area and perimeter of certain mosfets after extracting netlist from a layout done in magic ? @Tim Edwards

What version of magic? Magic used to calculate area and perimeter for each net, not each device, so if multiple devices were connected to a net, then all the source/drain area and perimeter would be put on one of the devices and the others would have zero. But some time ago (about a year, maybe?) I rewrote some of the code so that it extracts source and drain areas for each device independently.