title: How to grab a value corresponding to a particular date, if the date is before/after the dates in the table?
body: <p>I have a Google Sheet table with a number of inventory additions:</p>
  
  <pre><code>    Date    | Product | New Units | # Total Units 
   -----------|---------|-----------|--------------- 
    1/11/2017 | Coke    |        14 |            14 
    1/31/2017 | Pepsi   |         6 |             6 
    2/12/2017 | Coke    |         3 |            17 
    3/13/2017 | Coke    |        12 |            29 
    3/13/2017 | Pepsi   |        13 |            19
  </code></pre>
  
  <p>e.g., on Feb 12th 2017, I received 3 new units of Coke, for a total of 17 units. I'd like to be able to say for any given product and any given date, how many units of that product did I have on that date?</p>
  
  <p>For example, given the following list of dates in a separate sheet, based on the data above, I'd hope to see this output:</p>
  
  <pre><code>    Date    | Coke | Pepsi 
   -----------|------|------- 
    1/10/2017 |    0 |     0 
    1/11/2017 |   14 |     0 
    2/10/2017 |   14 |     6 
    2/15/2017 |   17 |     6 
    3/15/2017 |   29 |    19 
  </code></pre>
  
  <p>Is there a formula or formulas I could use to calculate values for B2:B6 and C2:C6?</p>