diff --git a/src/cal-period.scm b/src/cal-period.scm
index 3fa1dd4..5ff69eb 100644
--- a/src/cal-period.scm
+++ b/src/cal-period.scm
@@ -77,6 +77,14 @@
       (make-cal-month (+ 1900 (vector-ref d 5))
 		      (+ (vector-ref d 4) 1)))))
 
+ ;; Current month - if changed, we get the actual state for given month.
+ (define *current-day*
+   (make-parameter
+    (let ((d (seconds->local-time (current-seconds))))
+      (make-cal-day (+ 1900 (vector-ref d 5))
+		    (+ (vector-ref d 4) 1)
+		    (vector-ref d 3)))))
+
  ;; Creates a new period value with optional since and before
  ;; comments.
  (define (make-cal-period since before . args)