When the world economy is generally healthy, we can expect the greenback to weaken

The Bloomberg dollar index, which includes both emerging and developed markets, is at a 30-month low. 

If it dips much further, it will take out the low set in 2018. 

The next level to be tested would be the trough of 2014, before the currency began a sharp appreciation as the oil price plummeted

John Authers Bloomberg 2 december 2020

https://www.bloomberg.com/opinion/articles/2020-12-02/believe-in-global-reflation-the-dollar-does