Bell Curve - PPT to mention what Ideal Distribution of Bell Curve is?

I am working with a Travel Firm. We want to initiate Bell Curve System for mapping performance of our employees. We need to prepare a PPT on Performance Management wherein I need to mention what Ideal Distribution of Bell Curve is.
Request your help on the same. If someone has a default bell curve made or anyhelp with bell curve. Please Revert.

Bell Curve is an old method now, many a companies are no longer applying bell curve due to its complex nature, I would rather suggest you to use another performance method to map the performances.