Represent "All others" data for graph 2 and 3

Context

Graph 2 and 3 currently show the citation counts for the top 20 subjects and top 20 publishers, but users don't know anything about missing data.

Proposal

Show text below the graph to get users know that some data is excluded:

1. Graph 2: The visualization includes the top 20 subjects where metadata is available.
2. Graph 3: no text necessary since excluded data is negligible

Design

Implementation

Alternative approaches (if applicable)

Scheduling