title: Summary of data for each year in R
body: <p>I have a data with two columns. In one column it is date and in another column it is flow data. </p>
  
  <p>I was able to read the data as date and flow data. I used the following code:</p>
  
  <pre><code>creek &lt;- read.csv("creek.csv")
  library(ggplot2)
  creek[1:10,]
  colnames(creek) &lt;- c("date","flow")
  creek$date &lt;- as.Date(creek$date, "%m/%d/%Y")
  </code></pre>
  
  <p>The link to my data is <a href="https://www.dropbox.com/s/eqpena3nk82x67e/creek.csv" rel="nofollow">https://www.dropbox.com/s/eqpena3nk82x67e/creek.csv</a></p>
  
  <p>Now, I want to find the summary of each year. I want to especially know mean, median, maximum etc. </p>
  
  <p>Thanks. </p>
  
  <p>Regards, 
  Jdbaba</p>