[echelon]

Yes, but then they take that calculation to grant you a set number of shares (ISOs, RSUs, etc.) that doesn't change. The value of your award grows with the growth of the company.

ESPP-like programs, on the other hand, are always dollar denominated and exchanged at a set rate at the end of the offering period.

[joshuamorton]

GP is correct in that some companies (Stripe, MS, others) convert the dollars to shares at vest time, while others do so at grant time.

The first way makes employees lose out on an average of 2 years of stock growth.