Yuefu in Han Dynasty was mostly collected by the people. If we don't know the exact author, such as the famous works Shang Yang, Sang and Peacock Flying Southeast, we don't know who the author is.
New Yuefu appeared in the Tang Dynasty. The first poets were Du Fu, Jie Yuan, Wei and others. Later, Bai Juyi was the most famous. He wrote 50 new Yuefu poems and officially used the name "New Yuefu".