diff --git a/checker/rule.go b/checker/rule.go
index 6850730..7e91fb5 100644
--- a/checker/rule.go
+++ b/checker/rule.go
@@ -31,6 +31,7 @@ type issuerAgg struct {
 	code      string
 	msg       string
 	endpoints map[string]bool
+	count     int // number of certificates observed from this issuer
 }
 
 type allowList struct {
@@ -152,6 +153,7 @@ func (r *caaRule) Evaluate(ctx context.Context, obs sdk.ObservationGetter, opts
 			cur = &issuerAgg{sample: p, endpoints: map[string]bool{}}
 			agg[k] = cur
 		}
+		cur.count++
 		if severityRank(severity) >= severityRank(cur.severity) {
 			cur.severity = severity
 			cur.code = code
@@ -233,22 +235,23 @@ func (r *caaRule) Evaluate(ctx context.Context, obs sdk.ObservationGetter, opts
 			endpoints = append(endpoints, ep)
 		}
 		sort.Strings(endpoints)
-		meta := map[string]any{"endpoints": endpoints}
+		meta := map[string]any{"endpoints": endpoints, "cert_count": a.count}
 
+		certSuffix := fmt.Sprintf(" (%d certificate(s) checked)", a.count)
 		switch a.severity {
 		case SeverityCrit:
 			out = append(out, sdk.CheckState{
-				Status: sdk.StatusCrit, Message: a.msg, Code: a.code,
+				Status: sdk.StatusCrit, Message: a.msg + certSuffix, Code: a.code,
 				Subject: subject, Meta: meta,
 			})
 		case SeverityWarn:
 			out = append(out, sdk.CheckState{
-				Status: sdk.StatusWarn, Message: a.msg, Code: a.code,
+				Status: sdk.StatusWarn, Message: a.msg + certSuffix, Code: a.code,
 				Subject: subject, Meta: meta,
 			})
 		case SeverityInfo:
 			out = append(out, sdk.CheckState{
-				Status: sdk.StatusInfo, Message: a.msg, Code: a.code,
+				Status: sdk.StatusInfo, Message: a.msg + certSuffix, Code: a.code,
 				Subject: subject, Meta: meta,
 			})
 		default:
@@ -257,7 +260,7 @@ func (r *caaRule) Evaluate(ctx context.Context, obs sdk.ObservationGetter, opts
 				msg = "Certificate observed; no CAA records published"
 			}
 			out = append(out, sdk.CheckState{
-				Status: sdk.StatusOK, Message: msg, Code: CodeOK,
+				Status: sdk.StatusOK, Message: msg + certSuffix, Code: CodeOK,
 				Subject: subject, Meta: meta,
 			})
 		}