You’re reading Significant Digits, a daily digest of the numbers tucked inside the news.

4.1 percent

The share of Americans moving across county and state lines to pursue work has plummeted. In rural areas, for example, 4.1 percent of people moved across a county line in 2015. The rate was 7.7 percent in the late 1970s. [The Wall Street Journal]

65 – 68 degrees

Nighttime thermostat wars? It happens to the best of us. At first, it’s civil. Then it escalates. Before you know it, you’re digging through the drawer looking for duct tape to lock that temperature in place. So let’s settle this now: Room temps between 65 and 68 degrees are best for sleep. Match those temperature settings with a mattress that keeps you cool and you’ll be well on your way to getting some high quality Z’s. Sponsored by Casper

6 percent

Kraft Heinz, now managed by the renowned cost-cutters at 3G Capital, is trying to reinvent its Oscar Meyer hot dogs for a more health-conscious consumer. The reinvention might bring a 6 percent sales jump, according to the company’s market research, and they’re spending $10 million to build the new hot dogs. [Bloomberg]

36.5 opioid deaths

A new study is casting doubt on previous research suggesting that rising mortality rates among middle-aged white men is largely attributable to “deaths of despair.” Rather, the new study in the International Journal of Epidemiology suggests that metabolic diseases such as obesity and opioid addiction (which has seen drug related deaths jump from 1.4 deaths per 100,000 men in 1980 to 36.5 deaths per 100,000 men in 2014) are among the key factors. [Medical Xpress]

74 percent

Well then: A new Quinnipiac poll found that GOP Sen. John McCain, who last week cast a decisive vote to stop a partial repeal of the Affordable Care Act, received a 60 percent positive rating from independents and a 74 percent positive rating from Democrats. [Quinnipiac]

200 megawatts

Duke Energy is projecting that its solar power generation facilities across South Carolina will see their output drop from 2,500 megawatts to 200 megawatts during the forthcoming solar eclipse in August. The eclipse is expected to make a direct hit on South Carolina. [Duke Energy]

$47 billion

Total value of bitcoin, which is being split into two currencies: traditional bitcoin and a new spinoff product Bitcoin Cash, designed to be a more bleeding-edge financial technological asset compared to, you know, the old stodgy algorithmically generated code money of yesteryear. [Wired]

If you see a significant digit in the wild, send it to @WaltHickey.