The most straightforward way to qualify for the Employee Retention Credit is from a qualified revenue reduction during the qualification period of the program. Revenue reduction qualifications: 2020 – 50% reduction of gross sales for the 2020 quarter as compared to the same quarter in 2019. When/if the revenue reduction in 2020 gets back to 80% of the 2019 level, the qualification ends. 2021 – 20% reduction of gross sales for the 2021 quarter as compared to the same quarter in 2019 (or 2020 if you were not in business during the quarter in 2019). The alternative lookback option allows the business to use the previous quarter compared to the same 2019 quarter to qualify.