title: X axis labels tied to histogram bars instead of following separate rules
body: <p>When using a histogram with x as a POSIXct value, I'm not sure how you're supposed to line the ticks up with the binsize of the graph.</p>
  
  <p>Setting the tick size to the same as the binsize makes it line a bit off, but the offset adds onto each other until its no longer accurate.</p>
  
  <pre><code>bymonth &lt;- ggplot() +
    scale_x_datetime("", breaks = date_breaks("60 days"), labels = date_format("%m-%y")) + 
  
    ...
    lots of geom_rects for background colors
    ...
  
    theme(legend.title = element_blank()) + 
  
    geom_histogram(data=dat, aes(x = iso, fill = name), binwidth = 30*24*60*60, position = 'dodge')
  </code></pre>
  
  <p>I tried using <code>annotate()</code> as well as experimenting with the spacing of the tick but I think my approach here might be wrong in its own accord</p>
  
  <p>This leads to a graph looking something like this</p>
  
  <p><a href="https://i.stack.imgur.com/AXjRK.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/AXjRK.png" alt="image from https://i.imgur.com/73ZpG71.png"></a></p>
  
  <p>Which is quite annoying</p>