title: Percentile function across multiple arrays
body: <p>So I have this data in excel right now</p>
  
  <pre><code>  A             B           C
  2015-1        Test 1        23    
  2015-2        Test 1        12
  2015-3        Test 1        43
  2015-4        Test 1        32
  2015-5        Test 1        3
  2015-6        Test 1        90
  2015-1        Test 2        200
  2015-2        Test 2        123
  2015-3        Test 2        21
  2015-4        Test 2        40
  2015-5        Test 2        17
  2015-6        Test 2        138
  2015-1        Test 3        160
  2015-2        Test 3        55
  2015-3        Test 3        30
  2015-4        Test 3        74
  2015-5        Test 3        67
  2015-6        Test 3        89
  </code></pre>
  
  <p>Right now, I have it so that the user can look at the a specific time period, not necessarily all of the dates, of data, (for example, from 2015-1 to 2015-4). So when the user selects the date that they want, I want to take the percentile of the data(column C) at that date across <em>all</em> of the different test scenarios in column B. Right now there is only 3, but there will be up to 100 different test cases.  </p>
  
  <p>I know its possible to do =Percentile((test1_data,test2_data,test3_data),1), 
  but I'm going to have to do the percentile across over 100 difference test cases, and the way I have it set up now seems highly inefficient. Is there a way to do this without having to enter in all of the 100 different arrays by hand? </p>