title: PHPSpreadsheet not showing decimal numbers, despite using formatting
body: <p>I'm working on an Excel export where each row needs to have a percentage value, rounded to one decimal place. After exporting the spreadsheet, users need to be able to use those values for calculations inside the spreadsheet, hence why I can't simply format them as strings (or percentages, Excel doesn't like calculations using percentages for some reason). I've tried a few different things, but none of them work;</p>
  
  <pre><code>$sheet-&gt;getCell($coord)-&gt;setValueExplicit(
      $amount['percentage'],
      DataType::TYPE_NUMERIC
  );
  </code></pre>
  
  <p>in which <code>$coord</code> is the required cell (for example <code>'A1'</code>) and <code>$amount['percentage']</code> is a float like <code>45.2</code>.</p>
  
  <p>Another thing I've tried (and got straight from the PHPSpreadsheet documentation);</p>
  
  <pre><code>$sheet-&gt;setCellValue($coord, $amount['percentage']);
  $sheet-&gt;getStyle($coord)
      -&gt;getNumberFormat()
      -&gt;setFormatCode(NumberFormat::FORMAT_NUMBER_00);
  </code></pre>
  
  <p>In both cases the number is added as a whole number without decimal places (so <code>45</code> instead of <code>45.2</code>), the decimal number only shows when clicking the "Increase Decimal" button in excel.</p>
  
  <p>If I change <code>DataType::TYPE_NUMERIC</code> to <code>DataType::TYPE_STRING</code> the number is displayed the way I want, but since it's printed as a string it can't be used for further calculations.</p>
  
  <p>Is it at all possible to always display the decimal number after exporting?</p>