I am up for promotion this month and my supervisor has asked me to type up a reccomendation letter for HR stating why I feel I deserve this promotion. I feel my work habits and history show exactly why I deserve this promotion. Also is it not my supervisor's job to do this? Should this bother me or am I overreating? P.S. I have been with this bank for 9 years and have had several promotions and have never had to do this before.

Don't let it bother you at all. This isn't unusual. I just asked my staff to do the same thing so I could give her a big promotion.

Seeing her world through her eyes, and comparing it to the value I find in her work is always worthwhile. While I will edit her information prior to sending it to compensation committee, it pointed out some subtle but important things I frankly would have forgotten.

I am doing one for myself as well. My boss is a fabulous boss, but he's not involved in the day to day operations of my department. I can represent myself better to him by providing him with this information to share on my behalf with the balance of senior management.

Toot your horn in a clear and concise way and GOOD LUCK!!! Don't let it bother you at all

This is your chance to "toot your own horn". You may think they know how valuable you are and what your qualifications are, but maybe there's something they've overlooked or don't realize. Remind them.

Take the opportunity to tell them how great you are, what you could bring to the position, and maybe even ideas you have for improving a specific situation and / or bettering the company. Sell yourself to them. They're waiting to buy, but they want to know, straight from the person who knows best, what they'd be getting.

Who has a better idea of your accomplishments, you or your boss? I would have fallen all over myself lunging for such an opportunity...

I hope I get to even speak a few sentences next time I'm up for a promotion. Sounds like your boss wants to be sure every good thing that can be said about you gets said.

And also, bear in mind that many companies now want you to do your own performance review/evaluation. It's a new management style.
I would also love to have the chance! Good luck.