title: Combine calculated value with text in ggplot2 annotation
body: <p>I have a ggplot2 bar chart in which I would like to add an annotation that's part calculated value and part custom text.  I can't for the life of me think of the right search terms to use in SO to find an example.</p>
  
  <p>If I have a numerical array "LoadRecommentation", I want to be able to create an annotation as below, with the value from LoadRecommendation as well as custom text like "Loads".  The code below is clearly not going to work, but I'm not sure how to fix this.</p>
  
  <pre><code>ggplot(
    PowerDrawMelt, aes(x=MillNames, y=value, fill=variable)) +
    geom_bar(stat="identity", position = "identity", alpha=1) +
    annotate("text", x = 1, y = 1, label = "LoadRecommendation[3] + "Loads"")
  </code></pre>