mp</span> <span class='kw'>=</span> <span class='fu'>fill_backward</span>(<span class='no'>obs</span>))</div><div class='output co'>#&gt; # A tibble: 4 x 3
#&gt; # Groups:   id [2]
#&gt;      id   obs obs_imp
#&gt;   &lt;dbl&gt; &lt;dbl&gt;   &lt;dbl&gt;
#&gt; 1     1   1.2     1.2
#&gt; 2     1   4.8     4.8
#&gt; 3     2   2.5     2.5
#&gt; 4     2  NA      NA  </div></pre>
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