[myoung8]

Read the instructions first...

...decisions will include the amount we'll invest and the percent of the company we'd want for it. We usually invest $5000 + $5000n, where n is the number of participating founders (i.e. 2 founders get $15,000, 3 get $20,000), in return for between 2% and 10% of the company. The median is 6%.

[icky]

Most importantly:

The money itself is NOT the reason to sign up for YC.

[jdavid]

but the % share is a good reason to turn down the deal if you have other options. I just think it's to know what yc investors are told behind the curtain, and how much you are worth. It's nice to know what expectations you should live up to.