It seems to me that you haven't made any effort to find information in question, which is easily available online. To illustrate, just a very brief Internet search resulted in the following arguably relevant sources: SCImago Journal & Country Rank - International Science Ranking as well as Nature Index - Country Outputs. Note that Nature Index is a much less comprehensive resource, since it is based on "selected group of 82 high-quality science journals". Thus, it is likely less representative, though it might still be representative enough, depending on how representative those 82 journals are. On the other hand, SCImago Ranking is based on Scopus database and advertises the coverage of 5000+ publishers and citations across 239 countries.
Obviously, if you are serious about your research, you have to perform a comprehensive search for relevant sources (as well as relevant papers) and analyze their quality before using any of them to draw any conclusions.