How long would a Neomydium Magnet keep its magnetic strength if stored by itself in a box? I know it is better to attatch the magnet to something like a steel file cabinet to keep its strength, but let's assume the worst.
Thanks!

Neodymium magnets are unlike alnico magnets in that they don't need a keeper. Neodymium magnets are the most permanent of all magnets. They only lose about 1% of their strength every 10 years, so you will hardly notice. They are susceptible to temperature, but unless you are going over 175 degrees you are fine.

Thanks for the info!