Does the earths magnetic field reverse every year or so?

"The reversal rate for the earth's magnetic field has been varied over the ears. 72 million years ago the field has been reversed for 5 times in a million years."

Explanation:

Looking at the magnetic fingerprints locking that has been present in the ancient rock, we can predict that in the last 20 millions years the magnetic north and the south has been flipped roughly in every 200,000 to 300,000 years. The field gets deflected from the speeding particles towards the earth's poles. The magnetic field around the Earth is getting weakened and it is claimed by the scientist that it could have been gone in as little as 500 years.