It is used for setting the footer information
Example code
CComPtr<ISmpReport>m_SmpReport;
HRESULT hr=SmpReport.CoCreateInstance(CLSID_SmpReport);
BSTR bstrFooter1,bstrFooter2,bstrFooter3;
m_SmpReport->SetFooterInfo(bstrFooter1,bstrFooter2,bstrFooter3);