diff --git a/res-product/values/strings.xml b/res-product/values/strings.xml
index c824a6ab410..c8ec5bd29a6 100644
--- a/res-product/values/strings.xml
+++ b/res-product/values/strings.xml
@@ -576,11 +576,17 @@
     <!-- Battery Saver: Description for sticky battery saver preference [CHAR_LIMIT=NONE] -->
     <string name="battery_saver_sticky_description_new" product="device">Battery Saver turns off when your device charges above <xliff:g id="battery_percentage" example="80%">%1$s</xliff:g></string>
     <!-- [CHAR_LIMIT=NONE] Battery usage main screen footer content -->
-    <string name="battery_usage_screen_footer" product="default">Battery usage data is approximate and doesn\'t measure usage when phone is charging</string>
+    <string name="battery_usage_screen_footer_since_last_full_charge" product="default">Usage numbers are proportional to battery usage since last full charge and usage data is not measured when phone is charging</string>
     <!-- [CHAR_LIMIT=NONE] Battery usage main screen footer content -->
-    <string name="battery_usage_screen_footer" product="tablet">Battery usage data is approximate and doesn\'t measure usage when tablet is charging</string>
+    <string name="battery_usage_screen_footer_since_last_full_charge" product="tablet">Usage numbers are proportional to battery usage since last full charge and usage data is not measured when tablet is charging</string>
     <!-- [CHAR_LIMIT=NONE] Battery usage main screen footer content -->
-    <string name="battery_usage_screen_footer" product="device">Battery usage data is approximate and doesn\'t measure usage when device is charging</string>
+    <string name="battery_usage_screen_footer_since_last_full_charge" product="device">Usage numbers are proportional to battery usage since last full charge and usage data is not measured when device is charging</string>
+    <!-- [CHAR_LIMIT=NONE] Battery usage main screen footer content -->
+    <string name="battery_usage_screen_footer_of_timestamp" product="default">Usage numbers are proportional to battery usage of <xliff:g id="slot">%s</xliff:g> and usage data is not measured when phone is charging</string>
+    <!-- [CHAR_LIMIT=NONE] Battery usage main screen footer content -->
+    <string name="battery_usage_screen_footer_of_timestamp" product="tablet">Usage numbers are proportional to battery usage of <xliff:g id="slot">%s</xliff:g> and usage data is not measured when tablet is charging</string>
+    <!-- [CHAR_LIMIT=NONE] Battery usage main screen footer content -->
+    <string name="battery_usage_screen_footer_of_timestamp" product="device">Usage numbers are proportional to battery usage of <xliff:g id="slot">%s</xliff:g> and usage data is not measured when device is charging</string>
     <!-- Summary of preference to install certificates from SD card [CHAR LIMIT=NONE] -->
     <string name="credentials_install_summary" product="nosdcard">Install certificates from storage</string>
     <!-- Summary of preference to install certificates from SD card [CHAR LIMIT=NONE] -->
diff --git a/res/xml/power_usage_advanced.xml b/res/xml/power_usage_advanced.xml
index eaefe9df338..2a1a23c78fe 100644
--- a/res/xml/power_usage_advanced.xml
+++ b/res/xml/power_usage_advanced.xml
@@ -55,7 +55,6 @@
         <com.android.settingslib.widget.FooterPreference
             android:key="battery_usage_footer"
             android:selectable="false"
-            android:title="@string/battery_usage_screen_footer"
             settings:isPreferenceVisible="false"
             settings:searchable="false" />
 
diff --git a/src/com/android/settings/fuelgauge/batteryusage/BatteryUsageBreakdownController.java b/src/com/android/settings/fuelgauge/batteryusage/BatteryUsageBreakdownController.java
index 785c96ebe99..1bb3d018407 100644
--- a/src/com/android/settings/fuelgauge/batteryusage/BatteryUsageBreakdownController.java
+++ b/src/com/android/settings/fuelgauge/batteryusage/BatteryUsageBreakdownController.java
@@ -191,7 +191,7 @@ public class BatteryUsageBreakdownController extends BasePreferenceController
 
         showCategoryTitle(slotTimestamp);
         showSpinnerAndAppList();
-        showFooterPreference(isAllUsageDataEmpty);
+        showFooterPreference(isAllUsageDataEmpty, slotTimestamp);
     }
 
     // TODO: request accessibility focus on category title when slot selection updated.
@@ -204,11 +204,16 @@ public class BatteryUsageBreakdownController extends BasePreferenceController
         mRootPreference.setVisible(true);
     }
 
-    private void showFooterPreference(boolean isAllBatteryUsageEmpty) {
-        mFooterPreference.setTitle(mPrefContext.getString(
+    private void showFooterPreference(boolean isAllBatteryUsageEmpty, String slotTimestamp) {
+        mFooterPreference.setTitle(
                 isAllBatteryUsageEmpty
-                        ? R.string.battery_usage_screen_footer_empty
-                        : R.string.battery_usage_screen_footer));
+                        ? mPrefContext.getString(R.string.battery_usage_screen_footer_empty)
+                        : (slotTimestamp == null
+                                ? mPrefContext.getString(
+                                        R.string.battery_usage_screen_footer_since_last_full_charge)
+                                : mPrefContext.getString(
+                                        R.string.battery_usage_screen_footer_of_timestamp,
+                                        slotTimestamp)));
         mFooterPreference.setVisible(true);
     }