This is an important point concerning Effect Sizes: "I don't care if the results are significantly different, if the difference between the two samples is so small". People do get too wrapped up in statistical significance and forget about practical significance.
However, the relative difference (4.9%) is the relevant metric to be looking at as noted by "ezl" in a comment.
The article shouldn't have to spell out absolute differences in English sentences. The article mentions the important part (relative difference) in English sentences. The article includes the chart of the response rate by race the reader can see everything:
race response rate
black 11.01%
white 12.32%
hispanic 12.92%
However, the relative difference (4.9%) is the relevant metric to be looking at as noted by "ezl" in a comment.