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  1. PO
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    <p>Here's another approach:</p> <p><strong>Step 1.</strong> Select rows with <code>Date</code> values no later than the selected month, splitting every job's data into two partitions: the selected month data goes into the <code>New</code> partition, the rest goes into the <code>Old</code> one.</p> <p>Applied to your example, this would produce the following result set:</p> <pre> Job Date Percent_complete <b>recency</b> --- ---- ---------------- <b>-------</b> 1 1/5/2013 5 <b>Old </b> 2 1/10/2013 5 <b>Old </b> 2 1/25/2013 15 <b>Old </b> 2 2/15/2013 25 <b>New </b> 3 1/15/2013 5 <b>New </b> 1 2/10/2013 10 <b>New </b> 1 2/23/2013 20 <b>New </b> 1 2/24/2013 18 <b>New </b> 4 1/12/2013 40 <b>Old </b> </pre> <p><strong>Step 2.</strong> Rank rows in every partition in the descending order of <code>Date</code>:</p> <pre> Job Date Percent_complete recency <b>rnk</b> --- ---- ---------------- ------- <b>---</b> 1 1/5/2013 5 Old <b>1 </b> 2 1/10/2013 5 Old <b>2 </b> 2 1/25/2013 15 Old <b>1 </b> 2 2/15/2013 25 New <b>1 </b> 3 1/15/2013 5 New <b>1 </b> 1 2/10/2013 10 New <b>3 </b> 1 2/23/2013 20 New <b>2 </b> 1 2/24/2013 18 New <b>1 </b> 4 1/12/2013 40 Old <b>1 </b> </pre> <p><strong>Step 3.</strong> Get only rows with the rankings of 1:</p> <pre> Job Date Percent_complete recency rnk --- ---- ---------------- ------- --- 1 1/5/2013 5 Old 1 2 1/25/2013 15 Old 1 2 2/15/2013 25 New 1 3 1/15/2013 5 New 1 1 2/24/2013 18 New 1 </pre> <p><strong>Step 4.</strong> Pivot the percentages and default any <code>Old</code> NULLs to 0, and <code>New</code> to <code>Old</code>:</p> <pre> Job Old New --- --- --- 1 5 18 2 15 25 3 0 5 </pre> <p>The following query implements the above logic:</p> <pre><code>WITH partitioned AS ( SELECT Job, Date, Percent_complete, recency = CASE WHEN Date &gt;= '20130201' THEN 'NEW' ELSE 'Old' END FROM atable WHERE Date &lt; '20130301' ) , ranked AS ( SELECT Job, Date, Percent_complete, recency, rnk = ROW_NUMBER() OVER (PARTITION BY Job, recency ORDER BY Date DESC) FROM partitioned ) , filtered AS ( SELECT Job, Percent_complete, recency FROM ranked WHERE rnk = 1 ) , pivoted AS ( SELECT Job, Old = ISNULL(Old, 0), New = ISNULL(New, Old) FROM filtered PIVOT ( MAX(Percent_complete) FOR recency IN (Old, New) ) u ) SELECT * FROM pivoted ; </code></pre> <p>You can test this query <a href="http://sqlfiddle.com/#!3/c1d05/1" rel="nofollow">at SQL Fiddle</a>.</p>
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    1. POSelect oldest and newest value from a set of running values
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    1. USAndriy M
    1. USAndriy M
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    1. COThanks for your work. I'll look at it close at the beginning of the week and let you know how it does.
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      1. USMichael Nelson
    2. COI didn't pull it apart to figure out why, but it seems to be skipping around 100 of the jobs from the table of about 1500 distinct jobs. Thanks for all of your help, though.
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      1. USMichael Nelson
    3. COIt probably skips the newer jobs, those first logged *after* the reporting month. Anyway, if you are keen to just move on, I understand. Besides, the solution you've accepted is shorter/simpler than mine and therefore may be easier to maintain. And even that must be secondary to your just being happy with it (presumably).
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      1. USAndriy M
 

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