diff --git a/bigquery/compare-validation-reports.sql b/bigquery/compare-validation-reports.sql
new file mode 100644
index 000000000..509454cb7
--- /dev/null
+++ b/bigquery/compare-validation-reports.sql
@@ -0,0 +1,88 @@
+WITH
+  validation_report AS (
+    SELECT
+      *,
+      summary.validatorVersion
+    FROM
+      `${project_id}.data_analytics.gtfs_validation_reports_*`
+  ),
+  most_recent_reports AS (
+    SELECT
+      t1.*
+    FROM (
+      SELECT
+        *,
+        ROW_NUMBER() OVER (PARTITION BY feedId ORDER BY validatedAt DESC) AS row_num
+      FROM
+        validation_report
+      WHERE
+        summary.validatorVersion = current_version
+    ) AS t1
+    WHERE row_num = 1
+  ),
+  old_version_reports AS (
+    SELECT
+      t1.*
+    FROM (
+      SELECT
+        *,
+        ROW_NUMBER() OVER (PARTITION BY feedId ORDER BY validatedAt DESC) AS row_num
+      FROM
+        validation_report
+      WHERE
+        summary.validatorVersion = previous_version
+    ) AS t1
+    WHERE row_num = 1
+  ),
+  most_recent_notices AS (
+    SELECT
+      feedId,
+      datasetId,
+      notice.code,
+      notice.severity,
+      notice.totalNotices
+    FROM
+      most_recent_reports,
+      UNNEST(notices) AS notice
+  ),
+  old_version_notices AS (
+    SELECT
+      feedId,
+      datasetId,
+      notice.code,
+      notice.severity,
+      notice.totalNotices
+    FROM
+      old_version_reports,
+      UNNEST(notices) AS notice
+  ),
+  merged_reports AS (
+    SELECT
+      COALESCE(most_recent_notices.feedId, old_version_notices.feedId) AS feedId,
+      COALESCE(most_recent_notices.code, old_version_notices.code) AS code,
+      old_version_notices.severity AS severity_previous,
+      most_recent_notices.severity AS severity_current,
+      IFNULL(old_version_notices.totalNotices, 0) AS totalNotices_previous,
+      IFNULL(most_recent_notices.totalNotices, 0) AS totalNotices_current
+    FROM
+      old_version_notices
+    FULL OUTER JOIN
+      most_recent_notices
+    ON
+      old_version_notices.feedId = most_recent_notices.feedId
+      AND old_version_notices.code = most_recent_notices.code
+  )
+
+SELECT
+  feedId AS `Feed ID`,
+  code AS `Code`,
+  COALESCE(severity_previous, severity_current) AS `Severity`,
+  totalNotices_previous AS `Total Previous`,
+  totalNotices_current AS `Total Current`,
+  GREATEST(totalNotices_current - totalNotices_previous, 0) AS `New Notices`,
+  GREATEST(totalNotices_previous - totalNotices_current, 0) AS `Dropped Notices`
+FROM
+  merged_reports
+ORDER BY
+  `New Notices` DESC,
+  `Dropped Notices` DESC
diff --git a/infra/metrics/main.tf b/infra/metrics/main.tf
index ade1658c6..5c6ccf8e7 100644
--- a/infra/metrics/main.tf
+++ b/infra/metrics/main.tf
@@ -525,6 +525,38 @@ resource "google_cloudfunctions2_function" "gbfs_preprocessed_analytics" {
 
 }
 
+# 2.8 Compare validation reports routine
+resource "google_bigquery_routine" "compare_validation_reports_function" {
+  dataset_id = var.dataset_id
+  routine_id = "compare_validation_reports"
+  routine_type = "TABLE_VALUED_FUNCTION"
+
+  language = "SQL"
+  definition_body = templatefile("${path.module}/../../bigquery/compare-validation-reports.sql", {
+    project_id = var.project_id
+  })
+  arguments {
+    name = "previous_version"
+    data_type = jsonencode({ "typeKind" : "STRING" })
+  }
+  arguments {
+    name = "current_version"
+    data_type = jsonencode({ "typeKind" : "STRING" })
+  }
+  return_table_type = jsonencode({
+    "columns": [
+      { "name": "Feed ID", "type": { "typeKind": "STRING" } },
+      { "name": "Code", "type": { "typeKind": "STRING" } },
+      { "name": "Severity", "type": { "typeKind": "STRING" } },
+      { "name": "Total Previous", "type": { "typeKind": "INT64" } },
+      { "name": "Total Current", "type": { "typeKind": "INT64" } },
+      { "name": "New Notices", "type": { "typeKind": "INT64" } },
+      { "name": "Dropped Notices", "type": { "typeKind": "INT64" } }
+    ]
+  })
+}
+
+
 
 # Grant permissions to the service account
 # 1. BigQuery roles