The number of times they truly have free votes has probably not changed. There are issues in New Zealand that have been identified as conscience issues, really just by convention and tradition, things such as alcohol laws, same-sex marriage, abortion, gambling regulation, are issues on which members have been given a free vote by tradition and they continue to exercise that. In those circumstances where we have a true free vote, members are still called to the chamber with the bells and vote by going into the lobbies, and they will almost certainly not do that along party lines.
On May 17th, 2016. See this statement in context.