Governor Gretchen Whitmer's "Stay Home, Stay Safe" order went into effect on Tuesday, March 24. But it appears many Michiganders had already started staying home the week before, as it became clear that the COVID-19 outbreak had reached the state.

Read more: Is social distancing working? Here's what you need to know.

The image below shows the average movement of Michiganders over the past four weeks, based on cell phone location data gathered by Cuebiq. Darker blue indicates mobility closer to average, lighter colors indicate less travel.

From March 9 - 15, Michiganders were still moving as usual in their daily lives. That started to change the week of March 16, which is one week after the first cases of COVID-19 in Michigan were announced.

Once the stay home order was in place, movement decreased significantly, especially in southeastern counties, where the disease has hit the hardest so far. Last week, the majority of Michigan counties had below-average movement.

While some counties are reducing travel more than others, that doesn't necessarily mean that people in counties with more travel are ignoring social distancing guidelines. Cuebiq's Mobility Index is based only on movement of our devices, like cell phones, and doesn't tell us whether people observe social distancing practices like standing six feet apart in grocery store lines.

Different lifestyles in rural and urban areas also play an important role in how much people travel, and how much of that travel is voluntary. In more rural communities, people often have to travel further to do essential tasks like getting groceries or gas, meaning that they may need to continue traveling more than people in denser urban communities. Results from sparsely populated counties are also more likely to show some randomness from one week to the next.

People exposed to COVID-19 may not show symptoms of the disease for days or weeks, which means that decreases in cases and fatalities will lag behind the implementation of social distancing practices. Michiganders appear to be staying home, but the coming weeks will be important to gauge how well this is helping to contain the spread of COVID-19.