Acquisition trend aggregation fails

[yacc]

Moped::Errors::OperationFailure Error The operation: #<Moped::Protocol::Command @length=356 @request_id=5 @response_to=0 @op_code=2004 @flags=[:slave_ok] @full_collection_name="stripemetrics_production.$cmd" @skip=0 @limit=-1 @selector={:aggregate=>"customers", :pipeline=>[{"$project"=>{"customers"=>1, "year"=>{"$year"=>"$created"}, "month"=>{"$month"=>"$created"}, "week"=>{"$week"=>"$created"}, "day"=>{"$dayOfYear"=>"$created"}}}, {"$group"=>{"_id"=>{"year"=>"$year", "week"=>"$week"}, "count"=>{"$sum"=>1}}}]} @fields=nil> failed with error 16006: "exception: can't convert from BSON type EOO to Date" See https://github.com/mongodb/mongo/blob/master/docs/errors.md for details about this error. /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:78:in block in command' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:573:in[]' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:573:in block (3 levels) in flush' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:572:inmap' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:572:in block (2 levels) in flush' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:129:inensure_connected' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:568:in block in flush' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:583:inlogging' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:567:in flush' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:556:inprocess' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/node.rb:71:in command' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/session/context.rb:51:inblock in command' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/session/context.rb:105:in block in with_node' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/cluster.rb:250:inwith_secondary' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/session/context.rb:104:in with_node' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/session/context.rb:50:incommand' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/database.rb:76:in command' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/session.rb:78:incommand' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/moped-1.4.3/lib/moped/collection.rb:128:in aggregate' /home/deploy/www/stripemetrics/base/app/models/acquisition_trend.rb:19:inrefresh_weekly' /home/deploy/www/stripemetrics/base/app/models/acquisition_trend.rb:5:in refresh!' /usr/local/rvm/gems/ruby-1.9.3-p429@stripemetrics/gems/mongoid-3.1.2/lib/mongoid/relations/proxy.rb:143:inmethod_missing' /home/deploy/www/stripemetrics/base/app/workers/update_customer_trends.rb:12:in `perform'