diff --git a/bbstool.scm b/bbstool.scm
index 5555119..c3455b8 100644
--- a/bbstool.scm
+++ b/bbstool.scm
@@ -45,7 +45,7 @@ CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 	members-dir)
 
 ;; Print banner
-(print "bbstool 0.5 (c) 2023 Brmlab, z.s.")
+(print "bbstool 0.6 (c) 2023 Brmlab, z.s.")
 (newline)
 
 ;; Command-line options and configurable parameters
diff --git a/configuration.scm b/configuration.scm
index bb73b2a..0204174 100644
--- a/configuration.scm
+++ b/configuration.scm
@@ -30,7 +30,6 @@
  (
   *current-month*
   *member-file-context*
-  *member-default-joined*
   *member-suspend-max-months*
   )
 
@@ -50,10 +49,6 @@
  ;; Configuration of error reporting
  (define *member-file-context* (make-parameter 3))
 
- ;; Default as specified by the original implementation if the 'joined
- ;; key is missing in member file.
- (define *member-default-joined* (make-parameter (make-month 2015 1)))
-
  ;; How long the member can be suspended without any action required?
  (define *member-suspend-max-months* (make-parameter 24))
 
diff --git a/member-parser.scm b/member-parser.scm
index b67cbb6..d845c6d 100644
--- a/member-parser.scm
+++ b/member-parser.scm
@@ -132,7 +132,6 @@
    (apply
     member-record-sub-ensure
     mr 'info
-    'member (list (make-period (*member-default-joined*) #f))
     (join (map (lambda (mk) (list mk #f)) mandatory-keys))))
 
  ;; Pass 0: Removes any comments and removes any leading and trailing
diff --git a/member-record.scm b/member-record.scm
index 604228e..78c9323 100644
--- a/member-record.scm
+++ b/member-record.scm
@@ -45,6 +45,7 @@
   member-record-info
   member-missing-keys
   member-has-highlights?
+  member-record-usable?
   member-has-problems?
 
   member-destroyed?
@@ -221,16 +222,26 @@
  (define (member-has-errors? mr)
    (member-highlights-has-type? mr 'error))
 
+ ;; Absolutely required
+ (define (member-record-usable? mr)
+   (dict-has-key? (dict-ref mr 'info) 'member))
+
  ;; True if member record is OK
  (define (member-has-problems? mr)
    (or (member-has-errors? mr)
+       (not (member-record-usable? mr))
        (not (is-4digit-prime? (member-id mr)))))
 
  ;; Returns true if the member record represents non-existing
  ;; member. The *current-month* is a global parameter from period
  ;; module.
  (define (member-destroyed? mr)
-   (not (member-existing? mr)))
+   (and (not (member-existing? mr))
+	(let ((member (member-record-info mr 'member)))
+	  (if (null? member)
+	      #f
+	      (month>=? (*current-month*)
+			(period-since (car member)))))))
 
  ;; Generic period-based predicate
  (define ((member-period-predicate? key) mr)
diff --git a/members-base.scm b/members-base.scm
index a6a0415..3e72612 100644
--- a/members-base.scm
+++ b/members-base.scm
@@ -133,8 +133,9 @@
    (map (lambda (mr) (dict-ref (dict-ref mr 'info) 'nick)) mb))
 
  ;; Returns dictionary with statistics about the members base.
- (define (members-base-info mb)
-   (let* ((di0 (make-dict))
+ (define (members-base-info mb-arg)
+   (let* ((mb (filter-members-by-predicate mb-arg member-record-usable?))
+	  (di0 (make-dict))
 	  (di1 (dict-set di0 'invalid
 			 (filter-members-by-predicate mb
 						      (compose not is-4digit-prime? member-id))))
@@ -150,12 +151,15 @@
 	  (di7 (dict-set di6 'total mb)))
      di7))
 
+ (define (members-base-oldest-month mb)
+   (make-month 2015 1))
+
  ;; Returns a list two lists: keys, data.
  ;; Each data record contains values for all keys.
  (define (members-base-stats mb)
    (let ((keys '(month total active suspended students destroyed invalid)))
      (let mloop ((data '())
-		 (month (*member-default-joined*)))
+		 (month (members-base-oldest-month mb)))
        (if (month<? month (*current-month*))
 	   (let ((bi (parameterize ((*current-month* month))
 		       (members-base-info mb))))