Economists , however , may recall the old " hog cycle " that they learnt about in their first year of economics .
然而经济学家回想起他们在第一年经济学课程中学到的过去的“猪循环”。
Recently , the u.s. house of representatives took time out from fending off the world and exempted large cattle , dairy and hog producing operations from an environmental protection agency requirement for reporting greenhouse gas emissions .
A soft hog market , however , has many farmers pinching pennies , so it could take severe outbreaks , or ones close to home , to persuade them to spend money on a new vaccine .