Unfortunately, due to some miscalculations by the person who came up with this scheme, it's not entirely accurate.
According to more modern calculations, Jesus was probably born about four years before originally thought. Thus, if we wanted to be strictly accurate about measuring years by the birth of Christ, it's still 1997.
Of course, no one really wanted to do this, probably for the same reason that metric time is exactly the same as imperial time: while you can mess with spatial measurements, perception of time is simply too ingrained.
Perhaps as a result of this, the designation BCE, or "Before the Common Era," is becoming increasingly popular. Sure, it's politically correct, but strictly speaking it's more accurate too.