diff --git a/design/api.md b/design/api.md
index ee9e7bc..a67f649 100644
--- a/design/api.md
+++ b/design/api.md
@@ -89,13 +89,13 @@ Example response:
 {
   "days": {
     "2016-05-01": {
-      "end_time_usec": 131595516000000,
-      "start_time_usec": 131587740000000,
+      "end_time_90k": 131595516000000,
+      "start_time_90k": 131587740000000,
       "total_duration_90k": 52617609
     },
     "2016-05-02": {
-      "end_time_usec": 131603292000000,
-      "start_time_usec": 131595516000000,
+      "end_time_90k": 131603292000000,
+      "start_time_90k": 131595516000000,
       "total_duration_90k": 20946022
     }
   },
diff --git a/src/web.cc b/src/web.cc
index 8e440f5..da12741 100644
--- a/src/web.cc
+++ b/src/web.cc
@@ -316,9 +316,9 @@ void WebInterface::HandleJsonCameraDetail(evhttp_request *req,
   Json::Value days(Json::objectValue);
   std::string error_message;
   for (const auto &day : camera_row.days) {
-    int64_t start_time_usec;
-    int64_t end_time_usec;
-    if (!GetDayBounds(day.first, &start_time_usec, &end_time_usec,
+    int64_t start_time_90k;
+    int64_t end_time_90k;
+    if (!GetDayBounds(day.first, &start_time_90k, &end_time_90k,
                       &error_message)) {
       return evhttp_send_error(
           req, HTTP_INTERNAL,
@@ -326,8 +326,8 @@ void WebInterface::HandleJsonCameraDetail(evhttp_request *req,
     }
 
     Json::Value day_val(Json::objectValue);
-    day_val["start_time_usec"] = static_cast<Json::Int64>(start_time_usec);
-    day_val["end_time_usec"] = static_cast<Json::Int64>(end_time_usec);
+    day_val["start_time_90k"] = static_cast<Json::Int64>(start_time_90k);
+    day_val["end_time_90k"] = static_cast<Json::Int64>(end_time_90k);
     day_val["total_duration_90k"] = static_cast<Json::Int64>(day.second);
     days[day.first] = day_val;
   }