diff --git a/app/services/events/stores/clickhouse/unique_count_query.rb b/app/services/events/stores/clickhouse/unique_count_query.rb
index 5dbe6be4068..3421e625bff 100644
--- a/app/services/events/stores/clickhouse/unique_count_query.rb
+++ b/app/services/events/stores/clickhouse/unique_count_query.rb
@@ -30,7 +30,7 @@ def query
               GROUP BY property
             )
 
-            SELECT SUM(sum_adjusted_value) AS aggregation FROM event_values
+            SELECT coalesce(SUM(sum_adjusted_value), 0) AS aggregation FROM event_values
           SQL
         end
 
@@ -55,7 +55,7 @@ def prorated_query
               GROUP BY property, operation_type, timestamp
             )
 
-            SELECT SUM(period_ratio) as aggregation
+            SELECT coalesce(SUM(period_ratio), 0) as aggregation
             FROM (
               SELECT (#{period_ratio_sql}) AS period_ratio
               FROM event_values
@@ -87,7 +87,7 @@ def grouped_query
 
             SELECT
               #{group_names},
-              SUM(sum_adjusted_value) as aggregation
+              coalesce(SUM(sum_adjusted_value), 0) as aggregation
             FROM event_values
             GROUP BY #{group_names}
           SQL
@@ -119,7 +119,7 @@ def grouped_prorated_query
 
             SELECT
               #{group_names},
-              SUM(period_ratio) as aggregation
+              coalesce(SUM(period_ratio), 0) as aggregation
             FROM (
               SELECT
                 (#{grouped_period_ratio_sql}) AS period_ratio,
@@ -246,7 +246,15 @@ def period_ratio_sql
               operation_type = 'add',
               -- NOTE: duration in seconds between current add and next remove - using end of period as final boundaries if no remove
               toDecimal128(
-                (date_diff('seconds', timestamp, leadInFrame(timestamp, 1, toDateTime64(:to_datetime, 5, 'UTC')) OVER (PARTITION BY property ORDER BY timestamp ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING))),
+                (date_diff(
+                  'seconds',
+                  if(timestamp < toDateTime64(:from_datetime, 5, 'UTC'), toDateTime64(:from_datetime, 5, 'UTC'), timestamp),
+                  if(
+                    (leadInFrame(timestamp, 1, toDateTime64(:to_datetime, 5, 'UTC')) OVER (PARTITION BY property ORDER BY timestamp ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)) < toDateTime64(:from_datetime, 5, 'UTC'),
+                    toDateTime64(:to_datetime, 5, 'UTC'),
+                    leadInFrame(timestamp, 1, toDateTime64(:to_datetime, 5, 'UTC')) OVER (PARTITION BY property ORDER BY timestamp ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
+                  )
+                )),
                 :decimal_scale
               )
               /
@@ -265,7 +273,15 @@ def grouped_period_ratio_sql
               operation_type = 'add',
               -- NOTE: duration in seconds between current add and next remove - using end of period as final boundaries if no remove
               toDecimal128(
-                (date_diff('seconds', timestamp, leadInFrame(timestamp, 1, toDateTime64(:to_datetime, 5, 'UTC')) OVER (PARTITION BY #{group_names}, property ORDER BY timestamp ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING))),
+                (date_diff(
+                  'seconds',
+                  if(timestamp < toDateTime64(:from_datetime, 5, 'UTC'), toDateTime64(:from_datetime, 5, 'UTC'), timestamp),
+                  if(
+                    (leadInFrame(timestamp, 1, toDateTime64(:to_datetime, 5, 'UTC')) OVER (PARTITION BY #{group_names}, property ORDER BY timestamp ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)) < toDateTime64(:from_datetime, 5, 'UTC'),
+                    toDateTime64(:to_datetime, 5, 'UTC'),
+                    leadInFrame(timestamp, 1, toDateTime64(:to_datetime, 5, 'UTC')) OVER (PARTITION BY #{group_names}, property ORDER BY timestamp ASC ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING)
+                  )
+                )),
                 :decimal_scale
               )
               /
diff --git a/app/services/events/stores/clickhouse_store.rb b/app/services/events/stores/clickhouse_store.rb
index 83ce7e64a67..623c3567eb8 100644
--- a/app/services/events/stores/clickhouse_store.rb
+++ b/app/services/events/stores/clickhouse_store.rb
@@ -136,6 +136,7 @@ def prorated_unique_count
           [
             query.prorated_query,
             {
+              from_datetime:,
               to_datetime: to_datetime.ceil,
               decimal_scale: DECIMAL_SCALE,
             },
@@ -167,6 +168,7 @@ def grouped_prorated_unique_count
           [
             query.grouped_prorated_query,
             {
+              from_datetime:,
               to_datetime: to_datetime.ceil,
               decimal_scale: DECIMAL_SCALE,
             },
diff --git a/app/services/events/stores/postgres/unique_count_query.rb b/app/services/events/stores/postgres/unique_count_query.rb
index 54f54b525d7..2d0c0866689 100644
--- a/app/services/events/stores/postgres/unique_count_query.rb
+++ b/app/services/events/stores/postgres/unique_count_query.rb
@@ -30,7 +30,7 @@ def query
               GROUP BY property
             )
 
-            SELECT SUM(sum_adjusted_value) AS aggregation FROM event_values
+            SELECT COALESCE(SUM(sum_adjusted_value), 0) AS aggregation FROM event_values
           SQL
         end
 
@@ -55,7 +55,7 @@ def prorated_query
               GROUP BY property, operation_type, timestamp
             )
 
-            SELECT SUM(period_ratio) as aggregation
+            SELECT COALESCE(SUM(period_ratio), 0) as aggregation
             FROM (
               SELECT (#{period_ratio_sql}) AS period_ratio
               FROM event_values
@@ -87,7 +87,7 @@ def grouped_query
 
             SELECT
               #{group_names},
-              SUM(sum_adjusted_value) as aggregation
+              COALESCE(SUM(sum_adjusted_value), 0) as aggregation
             FROM event_values
             GROUP BY #{group_names}
           SQL
@@ -119,7 +119,7 @@ def grouped_prorated_query
 
             SELECT
               #{group_names},
-              SUM(period_ratio) as aggregation
+              COALESCE(SUM(period_ratio), 0) as aggregation
             FROM (
               SELECT
                 (#{grouped_period_ratio_sql}) AS period_ratio,
@@ -237,7 +237,21 @@ def period_ratio_sql
             CASE WHEN operation_type = 'add'
             THEN
               -- NOTE: duration in seconds between current event and next one - using end of period as final boundaries
-              EXTRACT(EPOCH FROM LEAD(timestamp, 1, :to_datetime) OVER (PARTITION BY property ORDER BY timestamp) - timestamp)
+              EXTRACT(
+                EPOCH FROM (
+                  (
+                    -- NOTE: if following event is older than the start of the period, we use the start of the period as the reference
+                    CASE WHEN (LEAD(timestamp, 1, :to_datetime) OVER (PARTITION BY property ORDER BY timestamp)) < :from_datetime
+                    THEN :from_datetime
+                    ELSE LEAD(timestamp, 1, :to_datetime) OVER (PARTITION BY property ORDER BY timestamp)
+                    END
+                  )
+                  - (
+                    -- NOTE: if events is older than the start of the period, we use the start of the period as the reference
+                    CASE WHEN timestamp < :from_datetime THEN :from_datetime ELSE timestamp END
+                  )
+                )
+              )
               /
               -- NOTE: full duration of the period
               #{charges_duration.days.to_i}
@@ -252,7 +266,21 @@ def grouped_period_ratio_sql
             CASE WHEN operation_type = 'add'
             THEN
               -- NOTE: duration in seconds between current event and next one - using end of period as final boundaries
-              EXTRACT(EPOCH FROM LEAD(timestamp, 1, :to_datetime) OVER (PARTITION BY #{group_names}, property ORDER BY timestamp) - timestamp)
+              EXTRACT(
+                EPOCH FROM (
+                  (
+                    -- NOTE: if following event is older than the start of the period, we use the start of the period as the reference
+                    CASE WHEN (LEAD(timestamp, 1, :to_datetime) OVER (PARTITION BY #{group_names}, property ORDER BY timestamp)) < :from_datetime
+                    THEN :from_datetime
+                    ELSE LEAD(timestamp, 1, :to_datetime) OVER (PARTITION BY #{group_names}, property ORDER BY timestamp)
+                    END
+                  )
+                  - (
+                    -- NOTE: if events is older than the start of the period, we use the start of the period as the reference
+                    CASE WHEN timestamp < :from_datetime THEN :from_datetime ELSE timestamp END
+                  )
+                )
+              )
               /
               -- NOTE: full duration of the period
               #{charges_duration.days.to_i}
diff --git a/app/services/events/stores/postgres_store.rb b/app/services/events/stores/postgres_store.rb
index 8fc4c5f28c5..8fd788fb791 100644
--- a/app/services/events/stores/postgres_store.rb
+++ b/app/services/events/stores/postgres_store.rb
@@ -93,6 +93,7 @@ def prorated_unique_count
           [
             query.prorated_query,
             {
+              from_datetime:,
               to_datetime: to_datetime.ceil,
             },
           ],
@@ -118,6 +119,7 @@ def grouped_prorated_unique_count
           [
             query.grouped_prorated_query,
             {
+              from_datetime:,
               to_datetime: to_datetime.ceil,
             },
           ],