Purges all ratings of a particular content block over a defined date/time range. 

This method can be accessed through the ContentRating.asmx file located in:

~/Workarea/webservices/WebServiceAPI/Content/ContentRating.asmx

[SoapHeader("AuthHeader")]
[SoapHeader("RequestInfoHeader")]
[WebMethod(MessageName = "PurgeContentRatings", Description = "")]
public void PurgeContentRatings(long contentid, DateTime startDate, DateTime endDate);

<SoapHeader("AuthHeader")>
<SoapHeader("RequestInfoHeader")>
<WebMethod(MessageName = "PurgeContentRatings", Description = "")>
Public Function PurgeContentRatings(contentid As long, startDate As DateTime, endDate As DateTime) As void