SharePoint Custom Web Part: How do I get my properties to export?

Hey Everyone,

I have built a sharepoint custom web part with a few properties that look like this:

[WebPartStorage( Storage.Shared )] [WebBrowsable( true ), WebDescription( "Benefit Mode" ), 
WebDisplayName( "Benefit Mode" ), Personalizable( PersonalizationScope.Shared )]
      public List<string> BenefitMode {
         get;
         set;
      }

I have set the ExportMode to All, but when I export no values are saving. What do I need to change?

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