So you can find the cited by counts in the API against the DOI querying just the DOI like here: http://0-api.crossref.org.lib.rivier.edu/works/10.1002/joc.4081. You would need to look for the is-referenced-by-count: value.
Let me know if you want examples of querying for this data by journal or perhaps a prefix basis.
You can’t query the REST API and get the citing works, that would be done via one of the methods from the link I sent in my first reply.
To get the citation counts based on an annual basis you would need to query the DOIs each year and make a note of the numbers, then query them the next year and compare the results. There is no way of retrieving when the matches were made and when I am afraid.
I hope this helps.