The 500K tests per day target is based on the Rockefeller Foundation National Testing Action Plan which says the U.S. needs to initially get to 3 million per week. The incidence adjusted target is based on a state's positivity rate. When the positivity rate is high, it means a state needs to be testing more. When the positivity rate is low, it means a state can test less, but should not dip below its proportion of the 500K tests per day that the US needs to do. The target positivity is 3% or lower. COVID+ rate is calculated for the 7-day rolling average of [new positive cases] / [total tests]. Increasing or decreasing describes the overall COVID+ trend. For detailed definitions see: https://www.covidexitstrategy.org/definitions-and-criteria