Present value vs. discount rate
The annuity's value falls as your discount rate rises. Where it crosses the cash line is the break-even rate.
Powerball & Mega Millions pay the annuity as 30 graduated payments (the first now, then 29 annual payments each 5% larger). We tax every payment at the combined rate and discount future payments to today's dollars. Estimates only — not financial or tax advice; real tax brackets, state rules, and investment returns vary.