diff --git a/plugins/system/cpu.go b/plugins/system/cpu.go
index 081a8ac73..d0b80bcc8 100644
--- a/plugins/system/cpu.go
+++ b/plugins/system/cpu.go
@@ -78,10 +78,9 @@ func (s *CPUStats) Gather(acc plugins.Accumulator) error {
 			continue
 		}
 
-		usage_idle := 100 * (cts.Idle - lastCts.Idle) / totalDelta
 		add(acc, "usage_user", 100*(cts.User-lastCts.User)/totalDelta, tags)
 		add(acc, "usage_system", 100*(cts.System-lastCts.System)/totalDelta, tags)
-		add(acc, "usage_idle", usage_idle, tags)
+		add(acc, "usage_idle", 100*(cts.Idle-lastCts.Idle)/totalDelta, tags)
 		add(acc, "usage_nice", 100*(cts.Nice-lastCts.Nice)/totalDelta, tags)
 		add(acc, "usage_iowait", 100*(cts.Iowait-lastCts.Iowait)/totalDelta, tags)
 		add(acc, "usage_irq", 100*(cts.Irq-lastCts.Irq)/totalDelta, tags)
@@ -89,7 +88,6 @@ func (s *CPUStats) Gather(acc plugins.Accumulator) error {
 		add(acc, "usage_steal", 100*(cts.Steal-lastCts.Steal)/totalDelta, tags)
 		add(acc, "usage_guest", 100*(cts.Guest-lastCts.Guest)/totalDelta, tags)
 		add(acc, "usage_guest_nice", 100*(cts.GuestNice-lastCts.GuestNice)/totalDelta, tags)
-		add(acc, "usage_busy", 100.0-usage_idle, tags)
 
 	}
 
diff --git a/plugins/system/system_test.go b/plugins/system/system_test.go
index 62f2e264d..c16f2e27b 100644
--- a/plugins/system/system_test.go
+++ b/plugins/system/system_test.go
@@ -153,7 +153,7 @@ func TestSystemStats_GenerateStats(t *testing.T) {
 	require.NoError(t, err)
 
 	numCPUPoints = len(acc.Points) - (preCPUPoints + numCPUPoints)
-	expectedCPUPoints = 21
+	expectedCPUPoints = 20
 	assert.Equal(t, numCPUPoints, expectedCPUPoints)
 
 	assertContainsTaggedFloat(t, acc, "user", 11.4, 0, cputags)
@@ -177,7 +177,6 @@ func TestSystemStats_GenerateStats(t *testing.T) {
 	assertContainsTaggedFloat(t, acc, "usage_steal", 0.2301, 0.0005, cputags)
 	assertContainsTaggedFloat(t, acc, "usage_guest", 4.8, 0.0005, cputags)
 	assertContainsTaggedFloat(t, acc, "usage_guest_nice", 2.2, 0.0005, cputags)
-	assertContainsTaggedFloat(t, acc, "usage_busy", 21.2301, 0.0005, cputags)
 
 	err = (&DiskStats{&mps}).Gather(&acc)
 	require.NoError(t, err)