diff --git a/app/controllers/api/pm/sprint_issues_controller.rb b/app/controllers/api/pm/sprint_issues_controller.rb
index b004d93d2..732ff524f 100644
--- a/app/controllers/api/pm/sprint_issues_controller.rb
+++ b/app/controllers/api/pm/sprint_issues_controller.rb
@@ -17,7 +17,8 @@ class Api::Pm::SprintIssuesController < Api::Pm::BaseController
     data = []
     curren_issues = @issues.group(:status_id, :due_date).count
     total_count = @issues.count
-    cardinality = BigDecimal.new(total_count) / BigDecimal.new(time_count)
+    cardinality = (total_count.zero? || time_count.zero?) ? 0 : total_count.to_f / time_count.to_f
+    # cardinality = BigDecimal.new(total_count) / BigDecimal.new(time_count)
     time_count.times do |x|
       e_time = start_time + x
       completed = curren_issues[[5, e_time]].to_i + curren_issues[[3, e_time]].to_i - @issues.where(pm_issue_type: 3, status_id: 3).size