diff --git a/frontend/src/metabase/qb/lib/actions.js b/frontend/src/metabase/qb/lib/actions.js
index d8b3e973be6ded522c3e0465573dfc179e1e9971..12d17e7e556e88dc28c98e81f228d6528264577a 100644
--- a/frontend/src/metabase/qb/lib/actions.js
+++ b/frontend/src/metabase/qb/lib/actions.js
@@ -121,7 +121,7 @@ export const drillDownForDimensions = dimensions => {
     if (timeDimensions.length === 1) {
         const column = timeDimensions[0].column;
         let nextUnit = UNITS[Math.max(0, UNITS.indexOf(column.unit) - 1)];
-        if (nextUnit) {
+        if (nextUnit && nextUnit !== column.unit) {
             return {
                 name: column.unit,
                 breakout: [