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                      ESG Report, Leading with Purpose
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                          pdf
                        
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                      2019 Annual Report
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                          pdf
                        
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                      2019 Annual Report Narrative Section
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                          pdf
                        
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                      2019 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2018 Annual Report
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                          pdf
                        
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                      2018 Annual Report Narrative Section
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                          pdf
                        
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                      2018 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2017 Annual Report
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                          pdf
                        
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                      2017 Annual Report Narrative Section
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                          pdf
                        
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                      2017 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2016 Annual Report
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                          pdf
                        
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                      2016 Annual Report Narrative Section
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                          pdf
                        
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                      2016 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2015 Annual Report
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                          pdf
                        
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                      2015 Annual Report Narrative Section
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                          pdf
                        
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                      2015 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2014 Annual Report
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                          Webcast
                        
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                      2014 Annual Report Narrative Section
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                          pdf
                        
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                      2014 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2013 Annual Report
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                          Webcast
                        
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                      2013 Annual Report Narrative Section
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                          pdf
                        
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                      2013 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2012 Annual Report (HTML)
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                          Webcast
                        
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                      2012 Annual Report Narrative Section
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                          pdf
                        
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                      2012 Annual Report Financial Section (10-K)
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                          pdf
                        
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                      2011 Annual Report (HTML)
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                          Webcast
                        
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                      2011 Annual Report Narrative Section
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                          pdf
                        
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                      2011 Annual Report Financial Section (10-K)
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                          pdf
                        
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