title: Using a conditional clause in excel
body: <p>I have a column in excel like this. I want a new column that selectively takes the 1st value, then the 4th value, then 8th value, then 12th, 15th,19th i.e. the 3rd value once and 4th values every two times. What type of conditional clause should i use. A little hint would be appreciated.</p>
  
  <pre><code>A                B
  0.3              0.3
  1.1              2.6
  2.0              4.7
  2.6              13.5
  2.7              17.4
  2.8              22.1
  3.6
  4.7
  5.4
  9.7
  12.0
  13.5
  15.9
  17.2
  17.4
  18.7
  19.4
  20.4
  22.1
  23.4
  27.1
  28.3
  </code></pre>