Interface aggregate chart (swql)

Hi guys,

I'm trying to essentially recreate the Interface Aggregate Chart via the API, but am not having much luck (though I though for a while that I was). My query is

SELECT DisplayName, Description, DateTime, InAveragebps, OutAveragebps, TotalBytes,

  TotalPackets, Averagebps, OutPercentUtil, InPercentUtil, PercentUtil, OutMinbps, OutMaxbps, InMinbps, InMaxbps

    FROM Orion.NPM.InterfaceTraffic WHERE InterfaceID=".$interfaceId." AND DateTime > GetUtcDate()-1

The problem is - all the data that comes back shows the same value for Min/Max/Avg for In and Out (ie. In Min = In Max = In Avg). How should I tweak this swql to get what I'm after?  Also - for the mods, you guys should consider putting together a 'cookbook' of potentially common queries and distribute it with your SDK

This is an example of the chart:

Thanks!