Your AGI is the Adjusted Gross Income as shown on the return for the prior year. If you did not file a prior year return, enter $0 for the AGI amount. If you do not know your AGI, you can request a transcript from the IRS for the prior year AGI amount.
If this is your first return that you have filed or if you did not file a return in the previous year, your prior year PIN will be left blank and your Prior Year AGI will be "$0".
When you use the same account (username) each year, the 5 digit PIN you created for your current return (signature) will automatically carry forward to your next year's return as the Prior Year PIN. Your Prior Year AGI will also carry forward.