Because articles or patents issued at the end of the year are often included at the beginning of the following year. Articles collected at the beginning of the year will have a higher citation rate than those collected at the end of the year. For example, today is March 3, 20201. Suppose you want to search for a topic in the past five years, in most cases, you will start with 20 16 1 instead of 2016mMarch 31. This search habit will make fewer articles exposed to search at the end of the year than at the beginning of the year. How different will the papers published at the end of the year be from those published at the beginning of the year? Suppose article A was published in February, 20 15, article B was published in June, 20 16, and article A will be published in February, 20 16, 20 17. Article B will be within the search time range of 60 months from 20 16 to 2020. Therefore, B is published one month later than A, but it can be found to be 1 1 month longer than A, so there will be a greater probability of being cited. In this way, because of the search, the papers at the end of the year are rarely cited, so we define it as CitationTrap.