title: rrdtool fetch output
body: <p>I want to get an average of last 7 days readings from rrd database. I am using the rrdtool fetch for the same then calculating the average. I ran the following commands:</p>
  
  <pre><code>&gt; rrdtool fetch  /var/www/cloudrrd1/Divya.rrd AVERAGE -r 300 -s -1days -e now | wc -l
  291
  &gt; rrdtool fetch  /var/www/cloudrrd1/Divya.rrd AVERAGE -r 300 -s -2days -e now | wc -l
  579
  &gt; rrdtool fetch  /var/www/cloudrrd1/Divya.rrd AVERAGE -r 300 -s -3days -e now | wc -l
  126
  &gt; rrdtool fetch  /var/www/cloudrrd1/Divya.rrd AVERAGE -r 300 -s -4days -e now | wc -l
  167
  &gt; rrdtool fetch  /var/www/cloudrrd1/Divya.rrd AVERAGE -r 300 -s -5days -e now | wc -l
  208
  &gt; rrdtool fetch  /var/www/cloudrrd1/Divya.rrd AVERAGE -r 300 -s -6days -e now | wc -l
  249
  &gt; rrdtool fetch  /var/www/cloudrrd1/Divya.rrd AVERAGE -r 300 -s -7days -e now | wc -l
  291
  </code></pre>
  
  <p>I am confused on the number of readings. Shouldn't it always increase with the increase in no. of days ? or am i doing something wrong ?</p>