Pull Saved Search Results to Custom Fields

Hello,

I'm trying to set a few different field values using a saved search scheduled to run every day - namely I'm trying to pull YTD Sales to a static field every day, and am also trying to pull the results of a 12 month rolling for an item.

I was looking at using

function findItemRollingandYTD()  {      var searchresults = nlapiSearchRecord('item', customsearch8, null,null);      var yTD = '';      var rolling = '';      for ( var i = 0; searchresults != null && i < searchresults.length; i++ )      {          var searchresult = searchresults[ i ];          yTD += searchresult.getValue( 'ytd' );          rolling += searchresult.getValue( '12monthrolling' );      }  }

which can easily pull the value for each of these fields, BUT because it does not appear to be possible to set the value anywhere. I was also considering pulling the values in this script and setting the values in a separate function BUT because this is simply iterating through all items my concern is that it wouldn't match with the correct items.