Good question. If you haven't done your 2019 taxes, you can use your 2018 return. Now, let's say in 2018 you made $50,000, and in 2019 you made $120,000. You're going to want to use your 2019 return so that your loan amount can be larger. You will have to do your taxes to do that. You will have to submit your taxes to be able to use your 2019 earnings to get the PPP loan.