diff --git a/reference/datetime/dateinterval.xml b/reference/datetime/dateinterval.xml
index b1292cf812..646492f0a2 100644
--- a/reference/datetime/dateinterval.xml
+++ b/reference/datetime/dateinterval.xml
@@ -68,6 +68,11 @@
integer
s
+
+ public
+ float
+ f
+
public
integer
@@ -148,6 +153,14 @@
+
+ f
+
+
+ Number of microseconds, as a fraction of a second.
+
+
+
invert
@@ -177,6 +190,28 @@
+
+ &reftitle.changelog;
+
+
+
+
+
+ &Version;
+ &Description;
+
+
+
+
+ 7.1.0
+ The f property was added.
+
+
+
+
+
+
+
&reference.datetime.entities.dateinterval;
diff --git a/reference/datetime/dateinterval/format.xml b/reference/datetime/dateinterval/format.xml
index 3093c79d04..b720bb1d62 100644
--- a/reference/datetime/dateinterval/format.xml
+++ b/reference/datetime/dateinterval/format.xml
@@ -112,6 +112,17 @@
Seconds, numeric
1, 3, 57
+
+ F
+ Microseconds, numeric, at least 6 digits with leading
+ 0
+ 007701, 052738, 428291
+
+
+ f
+ Microseconds, numeric
+ 7701, 52738, 428291
+
R
Sign "-" when negative, "+" when positive
@@ -152,6 +163,29 @@
+
+ &reftitle.changelog;
+
+
+
+
+
+ &Version;
+ &Description;
+
+
+
+
+ 7.1.0
+ The F and f format
+ characters were added.
+
+
+
+
+
+
+
&reftitle.examples;