"The ERC has been amended three separate times after it was originally enacted as part of the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) in March of 2020 by the Taxpayer Certainty and Disaster Relief Act of 2020 (Relief Act), the American Rescue Plan (ARPA) Act of 2021, and the Infrastructure Investment and Jobs Act (IIJA)."
Access the Chart Here
This chart will help you get a sense of the differences in 2020 vs. 2021: