"WASHINGTON — Hotter days mean less cold cash for Americans, according to a new study matching 40 years of temperatures to economics.

Days that averaged about 77 degrees ended up reducing people's income by about $5 a day when compared with days that were about 20 degrees cooler. A county's average economic productivity decreases by nearly 1 percent for every degree Fahrenheit that the average daily temperature is above 59, says a National Bureau of Economic Research working paper released Monday.

And, the study's authors predict, if the world continues on its current path of greenhouse gas emissions, even warmer temperatures later this century will squeeze the U.S. economy by tens of billions of dollars each year."

Seth Borenstein reports for the Associated Press December 15, 2014. [2]