If you want to use data to illustrate a current phenomenon or predict future trends, it is naturally not rigorous to use previous data. If you want to use data to illustrate an algorithm or test a mathematical model, you can use the data of previous years and the actual situation of that year to verify whether your algorithm or model is correct.

Originality rate is the proportion of self-written content in the submitted papers, plagiarism rate is the proportion of similar parts in the submitted papers, citation rate is the proportion of parts identified as references in the submitted papers, and similarity rate is the proportion of parts similar to all documents (including references) in the whole submitted papers.