diff --git a/Makefile b/Makefile
index 3e0038e..a60cdb8 100644
--- a/Makefile
+++ b/Makefile
@@ -143,7 +143,7 @@ utils.so: utils.o
 utils.o: utils.import.scm
 utils.import.scm: $(UTILS-SOURCES)
 
-PRIMES-SOURCES=primes.scm testing.import.scm
+PRIMES-SOURCES=primes.scm testing.import.scm utils.import.scm
 
 primes.so: primes.o
 primes.o: primes.import.scm
diff --git a/brmsaptool.scm b/brmsaptool.scm
index eba698b..47f3c6c 100644
--- a/brmsaptool.scm
+++ b/brmsaptool.scm
@@ -78,6 +78,7 @@ CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  (-print () "Print given member file"
 	 (-action- 'print-member-file))
  (-tests () "Run self-tests upon startup" (-run-tests?- #t))
+ (-idstats () "Returns information about available member ids" (-action- 'print-idstats))
  )
 
 ;; Run tests
@@ -127,4 +128,8 @@ CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 	  (print-member-source mr))
 	 (else
 	  (print "No member specified!"))))
+  ((print-idstats)
+   (newline)
+   (print-members-ids-stats MB)
+   (newline))
   )
diff --git a/member-file.scm b/member-file.scm
index 2070704..f6d07e5 100644
--- a/member-file.scm
+++ b/member-file.scm
@@ -99,7 +99,8 @@
       (print-source-listing lines (list highlight)
 			    (*member-file-context*)
 			    a:error a:default
-			    "" "" "...")))
+			    "" "" "...")
+      (newline)))
    (if (eq? (*member-file-check-syntax*) 'error)
        (exit 1)
        (list member-file-error-symbol
diff --git a/members-base.scm b/members-base.scm
index a77dce8..501211f 100644
--- a/members-base.scm
+++ b/members-base.scm
@@ -36,6 +36,8 @@
   members-base-stats
   print-members-base-info
   print-members-base-stats
+  get-free-members-ids
+  print-members-ids-stats
   members-base-tests!
   )
 
@@ -340,6 +342,31 @@
 	   (print month " " (string-intersperse (map number->string vals) " "))
 	   (loop (cdr rows)))))))
 
+ ;; Returns all free ids
+ (define (get-free-members-ids mb)
+   (let ((ids (list-members-ids mb)))
+     (filter
+      (lambda (id)
+	(not (member id ids)))
+      (gen-all-4digit-primes))))
+
+ ;; Prints statistics about allocated and unused valid/invalid IDs.
+ (define (print-members-ids-stats MB)
+   (print "Allocated IDs: "
+	  (length (list-members-ids MB))
+	  "/"
+	  (length (gen-all-4digit-primes))
+	  " ("
+	  (length (get-free-members-ids MB))
+	  " free)")
+   (let ((iids (filter (compose not is-4digit-prime?) (list-members-ids MB))))
+     (when (not (null? iids))
+       (print "      Invalid: "
+	      (length iids)
+	      " ("
+	      (string-intersperse (map number->string iids) ", ")
+	      ")"))))
+
  ;; Performs self-tests of this module.
  (define (members-base-tests!)
    (run-tests
diff --git a/primes.scm b/primes.scm
index a8b7860..3544f46 100644
--- a/primes.scm
+++ b/primes.scm
@@ -30,11 +30,13 @@
  (
   primes-tests!
   is-4digit-prime?
+  gen-all-4digit-primes
   )
 
  (import scheme
 	 (chicken base)
-	 testing)
+	 testing
+	 utils)
 
  ;; Checks whether given number is prime by checking the remainder of
  ;; the division by all primes less than square root of the number in
@@ -58,7 +60,7 @@
  (define (gen-primes less-than . init)
    (let loop ((primes (if (null? init)
 			  '(2)
-			  init))
+			  (car init)))
 	      (number 3))
      (if (< number less-than)
 	 (loop (if (check-prime primes number)
@@ -77,6 +79,11 @@
 	(<= n 9999)
 	(check-prime primes<100 n)))
 
+ ;; Generates all valid member ids
+ (define (gen-all-4digit-primes)
+   (filter is-4digit-prime?
+	   (gen-primes 10000 primes<100)))
+
  ;; Module self-tests.
  (define (primes-tests!)
    (run-tests