The Internet Assigned Numbers Authority (IANA) assigned the last IPv4 addresses to the five regions of the world’s Regional Internet Registries. In the meantime, a mere 0.2 percent of all Internet users worldwide rely on IPv6 connections. The vast majority of Internet users will continue to use the same IP addresses for the next couple of years. A major test of how well the world’s Internet users are ready for IPv6 will take place on June 8. Google says 99.95 percent of its users will not even notice the switch that day.
Source: https://www.pcworld.com/article/218742/why_care_so_much_about_ipv6.html