title: How to incrementally take average in Oracle SQL Or Python
body: <p>I am bit stuck with this not getting how do i proceed further</p>
  <p><strong>Assume I have below data in table</strong></p>
  <p><strong>Note</strong> : All the below <strong>column fields</strong> [<code>NAME , AGE , COURSE , MARKS</code>] are set to <code>VARCHAR2(50 CHAR)</code></p>
  <pre><code>NAME | AGE | COURSE | MARKS 
  A1   | ABC | MCA    | 5 
  B1   | XYZ | MBA    | 10
  C1   | PQR | MMS    | 14
  D1   | YST | CAT    | 18
  </code></pre>
  <p>Using below query I am able to get incremental sum , but not able to apply logic how to get incremental average</p>
  <p><strong>My Query :</strong></p>
  <pre><code>select c1.* , SUM(MARKS) Over (Order by c1.NAME) AS CUM_COUNT from EMP c1 order by c1.NAME ASC;
  </code></pre>
  <p><strong>Expected output :</strong></p>
  <pre><code>NAME | AGE | COURSE | MARKS | CUM_COUNT | AVGS_CNT      |
  A1   | ABC | MCA    | 5     | 5   | 5/1  = 5      |
  B1   | XYZ | MBA    | 10    | 15  | 15/2 = 7.5    |
  C1   | PQR | MMS    | 14    | 29  | 29/3 = 9.6    |
  D1   | YST | CAT    | 18    | 47  | 47/4 = 11.75  |
  </code></pre>
  <p><strong>Solution in oracle OR python appreciated</strong></p>
  <p><strong>Note :</strong> I have date in Oracle</p>
  <p><em>The reason behind asking this question as it was asked to me in interview</em></p>