Americans who lost their job or some of their income in 2020 should pay attention to a new, one-time provision that ensures they don’t lose access to valuable tax credits as well. These credits could be key to getting a refund. The “lookback” rule allows taxpayers to use either their 2019 or 2020 income, whichever is most beneficial, in order to get the most out of the Earned Income Tax Credit and the Child Tax Credit. These are considered two of the most valuable credits around for low- and moderate-income working families.