Welcome to WPSE. Based on the additional information you provided, static pages with the list of users changing only once per year, I would recommend simply using the built-in “Password Protected” publishing option.
The Publish metabox (typically in the top right corner of the page editor) has a few options beyond the default public visibility. Simply click “edit” to expand the options. See screenshot attached.
Each page published this way can have a unique password that is only shared with the user needing to view the content.