How to Get User Contribution Stats By Area

I'm interested of getting user contribution statistics for a particular region. For example, like it is done on http://osm.svimik.com/.

I looked through related questions, but all seems to be about contributions for particular user.

It looks like that using newer keyword for Overpass API should almost do the trick:

node
  (newer:"2017-10-24T07:00:00Z")     // adjust date as needed
  ({{bbox}})->.newnodes;

// Output
.newnodes out meta;

But how to tell the API to look for changes only for particular country? It is connected with area keyword, but it's not clear how to use it (the Overpass API is tricky). Also it is not clear, how to detect what was really done in resulting data:

 <node id="33191091" lat="54.6025991" lon="25.3133923" version="8" timestamp="2017-10-25T10:45:54Z" changeset="53232321" uid="60129" user="..."/>
  <node id="34224031" lat="54.6878381" lon="25.4908757" version="5" timestamp="2017-10-25T17:00:45Z" changeset="53240840" uid="60129" user="..."/>

It's only a list of nodes (and tags sometimes) and it's not clear if those nodes (tags, etc.) were just created, or edited, or moved.

On the whole, does anybody have a good example for something similar or a good explanation of how to use such queries. Also these queries are performance-consuming for the server, so probably I need to manage to run them locally somehow.