diff --git a/api/api.hh b/api/api.hh
index 65efc9d3b6..7f85da252e 100644
--- a/api/api.hh
+++ b/api/api.hh
@@ -111,13 +111,13 @@ inline double pow2(double a) {
 
 inline httpd::utils_json::histogram add_histogram(httpd::utils_json::histogram res,
         const utils::ihistogram& val) {
-    if (val.count == 0) {
-        return res;
-    }
     if (!res.count._set) {
         res = val;
         return res;
     }
+    if (val.count == 0) {
+        return res;
+    }
     if (res.min() > val.min) {
         res.min = val.min;
     }