16 years ago, Hurricane Katrina displaced roughly 1.3 million people, according to FEMA (see map). For Hurricane Ida, more people "hunkered down" as they say, but many evacuated or have been leaving since the storm hit. I will do a map like this for Ida if I get the data.
Hurricane Ida Sunday morning satellite loop before landfall at Port Fourchon near Grand Isle. Forecasted to track north between Baton Rouge and New Orleans.