diff --git a/contrib/pg_walinspect/pg_walinspect--1.0.sql b/contrib/pg_walinspect/pg_walinspect--1.0.sql
index 4243516d8a..08b3dd5556 100644
--- a/contrib/pg_walinspect/pg_walinspect--1.0.sql
+++ b/contrib/pg_walinspect/pg_walinspect--1.0.sql
@@ -80,13 +80,13 @@ CREATE FUNCTION pg_get_wal_stats(IN start_lsn pg_lsn,
     IN  per_record boolean DEFAULT false,
     OUT "resource_manager/record_type" text,
     OUT count int8,
-    OUT count_percentage float4,
+    OUT count_percentage float8,
     OUT record_size int8,
-    OUT record_size_percentage float4,
+    OUT record_size_percentage float8,
     OUT fpi_size int8,
-    OUT fpi_size_percentage float4,
+    OUT fpi_size_percentage float8,
     OUT combined_size int8,
-    OUT combined_size_percentage float4
+    OUT combined_size_percentage float8
 )
 RETURNS SETOF record
 AS 'MODULE_PATHNAME', 'pg_get_wal_stats'
@@ -102,13 +102,13 @@ CREATE FUNCTION pg_get_wal_stats_till_end_of_wal(IN start_lsn pg_lsn,
     IN  per_record boolean DEFAULT false,
     OUT "resource_manager/record_type" text,
     OUT count int8,
-    OUT count_percentage float4,
+    OUT count_percentage float8,
     OUT record_size int8,
-    OUT record_size_percentage float4,
+    OUT record_size_percentage float8,
     OUT fpi_size int8,
-    OUT fpi_size_percentage float4,
+    OUT fpi_size_percentage float8,
     OUT combined_size int8,
-    OUT combined_size_percentage float4
+    OUT combined_size_percentage float8
 )
 RETURNS SETOF record
 AS 'MODULE_PATHNAME', 'pg_get_wal_stats_till_end_of_wal'
diff --git a/contrib/pg_walinspect/pg_walinspect.c b/contrib/pg_walinspect/pg_walinspect.c
index 2f51a8dec4..38fb4106da 100644
--- a/contrib/pg_walinspect/pg_walinspect.c
+++ b/contrib/pg_walinspect/pg_walinspect.c
@@ -430,13 +430,13 @@ FillXLogStatsRow(const char *name,
 
 	values[i++] = CStringGetTextDatum(name);
 	values[i++] = Int64GetDatum(n);
-	values[i++] = Float4GetDatum(n_pct);
+	values[i++] = Float8GetDatum(n_pct);
 	values[i++] = Int64GetDatum(rec_len);
-	values[i++] = Float4GetDatum(rec_len_pct);
+	values[i++] = Float8GetDatum(rec_len_pct);
 	values[i++] = Int64GetDatum(fpi_len);
-	values[i++] = Float4GetDatum(fpi_len_pct);
+	values[i++] = Float8GetDatum(fpi_len_pct);
 	values[i++] = Int64GetDatum(tot_len);
-	values[i++] = Float4GetDatum(tot_len_pct);
+	values[i++] = Float8GetDatum(tot_len_pct);
 
 	Assert(i == ncols);
 }
diff --git a/doc/src/sgml/pgwalinspect.sgml b/doc/src/sgml/pgwalinspect.sgml
index de63a70965..1a1bee7d6a 100644
--- a/doc/src/sgml/pgwalinspect.sgml
+++ b/doc/src/sgml/pgwalinspect.sgml
@@ -164,13 +164,13 @@ postgres=# select start_lsn, end_lsn, prev_lsn, xid, resource_manager, record_ty
                        per_record boolean DEFAULT false,
                        "resource_manager/record_type" OUT text,
                        count OUT int8,
-                       count_percentage OUT float4,
+                       count_percentage OUT float8,
                        record_length OUT int8,
-                       record_length_percentage OUT float4,
+                       record_length_percentage OUT float8,
                        fpi_length OUT int8,
-                       fpi_length_percentage OUT float4,
+                       fpi_length_percentage OUT float8,
                        combined_size OUT int8,
-                       combined_size_percentage OUT float4)
+                       combined_size_percentage OUT float8)
       returns setof record
      </function>
     </term>
@@ -241,13 +241,13 @@ postgres=# select * from pg_get_wal_stats('0/14AFC30', '0/15011D7', true) where
                                        per_record boolean DEFAULT false,
                                        "resource_manager/record_type" OUT text,
                                        count OUT int8,
-                                       count_percentage OUT float4,
+                                       count_percentage OUT float8,
                                        record_length OUT int8,
-                                       record_length_percentage OUT float4,
+                                       record_length_percentage OUT float8,
                                        fpi_length OUT int8,
-                                       fpi_length_percentage OUT float4,
+                                       fpi_length_percentage OUT float8,
                                        combined_size OUT int8,
-                                       combined_size_percentage OUT float4)
+                                       combined_size_percentage OUT float8)
       returns setof record
      </function>
     </term>