Too hot, too cold, or just right? Turns out our economic productivity depends on finding a Goldilocks-like, perfect ambient temperature (of all things.)

According to Fortune, researchers at Stanford University and the University of California found per capita GDP growth reaches its maximum when a country's average temperature is about 55 degrees Fahrenheit.

"Decrease or increase the temperature and there's a significant negative impact on economic growth," writes Fortune's Erik Sherman. "Hello global warming, goodbye prosperity."

But we don't need to wait for a Waterworld-esque post-apocalyptic scenario to see the effects of temperature on productivity. Weirdly, even though hotter temps outside correlate with lower GDP, the best way to keep your employees workin' hard as opposed to hardly workin', is to keep the office nice and cozy.

"Cornell University researchers conducted a study that involved tinkering with the thermostat of an insurance office," reports Fast Company. "When temperatures were low (68 degrees, to be precise), employees committed 44% more errors and were less than half as productive as when temperatures were warm (a cozy 77 degrees) [...] When our body's temperature drops, we expend energy keeping ourselves warm, making less energy available for concentration, inspiration, and insight."

Layers, clearly, are the way of the future.

h/t Fast Company, Fortune.