CUPERTINO (CBS SF / CNN) — Last month, as Covid-19 cases increased in Texas and Arizona, Apple opted to shut stores in those states. Shortly after, the states themselves would either pause or roll back their reopenings.

The retail stores of America’s most valuable company have arguably become something of a barometer for how the pandemic is affecting different parts of the country — and the start and stop cycle of reopenings in various regions.

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Apple has a vast footprint in the United States, with 271 stores across the country in nearly every stateAnd with an unrivaled cash pile, the company can afford to be more reactive, closing stores sooner and keeping them closed longer, if need be.

Apple shuttered all its US stores in mid March, reopened a little over 100 of them in late May and then re-closed more than 70 of those starting mid-June, including all the outlets in Florida and Texas.

CNN Business built a map to track Apple Store closures across the US, offering another window into the ongoing health crisis — and the health of the country’s economy.

According to CNN’s map, states that have no Apple stores open include Arizona, Florida, Idaho, Iowa, Louisiana, Mississippi, Nebraska Oklahoma, South Carolina, Texas and Utah. While most stores in California are open, stores in and around Los Angeles remain closed.

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Map of closed Apple stores as of July 8, 2020. (CNN)

There is a precedent for using man-made establishments to help track the impact of natural disasters.

In 2004, an official at the Federal Emergency Management Agency (FEMA) was tracking the damage from a hurricane in Florida when he realized that the breakfast chain Waffle House could serve as an indicator of how badly an area was hit. Waffle House restaurants are known for being open 24/7 all year round, and reopening quickly — with a limited menu if necessary — after being forced to close because of a storm.

Thus, the Waffle House Index was born. And while FEMA uses its closures mainly to track storm damage, the restaurant chain hasn’t been immune to coronavirus either — it recently shut 420 of its nearly 2,000 stores because of the pandemic, but kept others open in a limited capacity.

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