Small multiples; tooltips pending (hopefully)

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<title>ISBN counts, 2002-2012</title>
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/* testing: */

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<header>
<h1>ISBN counts for print adult nonfiction books, 2002&ndash;2012</h1>
<h2>By the subject reported by Bowker customers when registering a book's ISBN</h2>

<p>According to Wikipedia, &ldquo;...Bowker provides bibliographic information on published works to the book trade, including publishers, booksellers, libraries, and individuals... Bowker is the exclusive U.S. agent for issuing International Standard Book Numbers (ISBNs), a universal method of identifying books in print.&rdquo; <span class="small">(<a href = "https://en.wikipedia.org/wiki/R.R._Bowker">https://en.wikipedia.org/wiki/R.R._Bowker</a>, accessed July 31, 2015)</span></p>
<p>Additional books are classified under &ldquo;non-traditional&rdquo; or &ldquo;unclassified;&rdquo; these are not included in this chart. These ISBNs ranged in count from 247,777 to 2,042,840 per year during this ten-year period.</p>
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<div id="source">
<p>Source: <a href="https://www.bowker.com/documents/isbn-output-report-2002-2013.html">https://www.bowker.com/documents/isbn-output-report-2002-2013.html</a></p>
</div>

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