Message-ID: <OF4B15C1CE.68F8AB10-ON862578F6.007B5274-862578F6.007BC171@usgs.gov>
Date: 2011-08-24T22:29:33Z
From: Jean V Adams
Subject: Creating new variable with maximum visit date by group_id
In-Reply-To: <SNT125-W102A094F7BE06CC9E612FE2110@phx.gbl>
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