diff --git a/src/lib/commands/coll.c b/src/lib/commands/coll.c
index c744e240..941b2d51 100644
--- a/src/lib/commands/coll.c
+++ b/src/lib/commands/coll.c
@@ -57,8 +57,6 @@ coll(void)
     struct lonstr loan;
     struct sctstr sect;
     coord x, y;
-    long due;
-    long last;
     long rdur;
     long xdur;
     double rate;
@@ -82,19 +80,21 @@ coll(void)
     /* If we got here, we check to see if it's been defaulted on.  We
        already know it's owed to this player. */
     (void)time(&now);
-    due = loan.l_duedate;
-    if (now <= due) {
+    /*
+     * split duration now - l_lastpay into regular (up to l_duedate)
+     * and extended (beyond l_duedate)
+     */
+    rdur = loan.l_duedate - loan.l_lastpay;
+    xdur = now - loan.l_duedate;
+    if (rdur < 0) {
+	xdur += rdur;
+	rdur = 0;
+    }
+    if (xdur <= 0) {
 	pr("There has been no default on loan %d\n", arg);
 	return RET_FAIL;
     }
-    last = loan.l_lastpay;
-    if (last < due && due < now) {
-	rdur = due - last;
-	xdur = now - due;
-    } else if (due < last) {
-	rdur = 0;
-	xdur = now - last;
-    }
+
     rate = loan.l_irate / (loan.l_ldur * 8.64e6);
 
 /* changed following to avoid overflow 3/27/89 bailey@math-cs.kent.edu
diff --git a/src/lib/commands/fina.c b/src/lib/commands/fina.c
index 93aaf01f..b80cce07 100644
--- a/src/lib/commands/fina.c
+++ b/src/lib/commands/fina.c
@@ -56,8 +56,6 @@ fina(void)
     int xdur;
     double rate;
     double amt;
-    time_t due;
-    time_t last;
 
     if (!opt_LOANS) {
 	pr("Loans are not enabled.\n");
@@ -73,26 +71,19 @@ fina(void)
     while (nxtitem(&ni, (s_char *)&loan)) {
 	if (loan.l_status != LS_SIGNED)
 	    continue;
-	due = loan.l_duedate;
-	last = loan.l_lastpay;
-	rdur = 0;
-	xdur = 0;
-	if (now < due) {
-	    rdur = now - last;
-	    xdur = 0;
-	}
-	if (last < due && due < now) {
-	    rdur = due - last;
-	    xdur = now - due;
-	}
-	if (due < last) {
+	/*
+	 * split duration now - l_lastpay into regular (up to l_duedate)
+	 * and extended (beyond l_duedate)
+	 */
+	rdur = loan.l_duedate - loan.l_lastpay;
+	xdur = now - loan.l_duedate;
+	if (rdur < 0) {
+	    xdur += rdur;
 	    rdur = 0;
-	    xdur = now - last;
 	}
-	if (loan.l_ldur == 0) {
-	    logerror("loan #%d has zero duration", ni.cur);
+
+	if (CANT_HAPPEN(loan.l_ldur == 0))
 	    continue;
-	}
 	rate = loan.l_irate / (loan.l_ldur * 8640000.0);
 
 /* changed following to avoid overflow 3/27/89 bailey@math-cs.kent.edu
diff --git a/src/lib/commands/repa.c b/src/lib/commands/repa.c
index 24dfa342..c22a96b1 100644
--- a/src/lib/commands/repa.c
+++ b/src/lib/commands/repa.c
@@ -50,8 +50,6 @@ repa(void)
     int loan_num;
     long payment;
     long owe;
-    long due;
-    long last_payment;
     long normaltime;
     long doubletime;
     double rate_per_sec, amt;
@@ -76,20 +74,17 @@ repa(void)
 	return RET_FAIL;
     }
     (void)time(&now);
-    due = loan.l_duedate;
-    last_payment = loan.l_lastpay;
-    if (now < due) {
-	normaltime = now - last_payment;
-	doubletime = 0;
-    }
-    if (last_payment < due && due < now) {
-	normaltime = due - last_payment;
-	doubletime = now - due;
-    }
-    if (due < last_payment) {
+    /*
+     * split duration now - l_lastpay into regular (up to l_duedate)
+     * and extended (beyond l_duedate)
+     */
+    normaltime = loan.l_duedate - loan.l_lastpay;
+    doubletime = now - loan.l_duedate;
+    if (normaltime < 0) {
+	doubletime += normaltime;
 	normaltime = 0;
-	doubletime = now - last_payment;
     }
+
     rate_per_sec = loan.l_irate /
 	((double)loan.l_ldur * SECS_PER_DAY * 100.0);
 
diff --git a/src/lib/commands/shark.c b/src/lib/commands/shark.c
index b9827a8f..9f0adf22 100644
--- a/src/lib/commands/shark.c
+++ b/src/lib/commands/shark.c
@@ -55,8 +55,6 @@ shark(void)
     struct lonstr loan;
     struct natstr *natp;
     struct natstr *oldie;
-    long due;
-    long last;
     long rdur;
     long xdur;
     double rate;
@@ -85,19 +83,21 @@ shark(void)
     }
     /* If we got here, we check to see if it's been defaulted on. */
     (void)time(&now);
-    due = loan.l_duedate;
-    if (now <= due) {
+    /*
+     * split duration now - l_lastpay into regular (up to l_duedate)
+     * and extended (beyond l_duedate)
+     */
+    rdur = loan.l_duedate - loan.l_lastpay;
+    xdur = now - loan.l_duedate;
+    if (rdur < 0) {
+	xdur += rdur;
+	rdur = 0;
+    }
+    if (xdur <= 0) {
 	pr("There has been no default on loan %d\n", arg);
 	return RET_FAIL;
     }
-    last = loan.l_lastpay;
-    if (last < due && due < now) {
-	rdur = due - last;
-	xdur = now - due;
-    } else if (due < last) {
-	rdur = 0;
-	xdur = now - last;
-    }
+
     rate = loan.l_irate / (loan.l_ldur * 8.64e6);
 
     owed = ((rdur * rate) + (xdur * rate * 2.0) + 1.0);
diff --git a/src/lib/subs/disloan.c b/src/lib/subs/disloan.c
index a0b95482..625de08c 100644
--- a/src/lib/subs/disloan.c
+++ b/src/lib/subs/disloan.c
@@ -54,8 +54,6 @@ int
 disloan(int n, register struct lonstr *loan)
 {
     time_t now;
-    time_t due;
-    time_t lastpaydate;
     time_t normaltime;
     time_t doubletime;
     time_t accept;
@@ -85,20 +83,18 @@ disloan(int n, register struct lonstr *loan)
 	pr("Loan must be accepted by %s", ctime(&accept));
 	return 1;
     }
-    due = loan->l_duedate;
-    lastpaydate = loan->l_lastpay;
-    if (now < due) {
-	normaltime = now - lastpaydate;
-	doubletime = 0;
-    }
-    if (lastpaydate < due && due < now) {
-	normaltime = due - lastpaydate;
-	doubletime = now - due;
-    }
-    if (due < lastpaydate) {
+
+    /*
+     * split duration now - l_lastpay into regular (up to l_duedate)
+     * and extended (beyond l_duedate)
+     */
+    normaltime = loan->l_duedate - loan->l_lastpay;
+    doubletime = now - loan->l_duedate;
+    if (normaltime < 0) {
+	doubletime += normaltime;
 	normaltime = 0;
-	doubletime = now - lastpaydate;
     }
+
     rate = ((double)loan->l_irate / 100.0) / (loan->l_ldur * SECS_PER_DAY);
     owe = ((double)loan->l_amtdue *
 	   (((double)normaltime * rate + 1.0) +
@@ -107,7 +103,7 @@ disloan(int n, register struct lonstr *loan)
     pr("Amount due (if paid now) $%.2f", owe);
     if (doubletime == 0) {
 	pr(" (if paid on due date) $%.2f\n",
-	   loan->l_amtdue * ((due - lastpaydate) * rate + 1.0));
+	   loan->l_amtdue * ((loan->l_duedate - loan->l_lastpay) * rate + 1.0));
 	pr("Due date is %s", ctime(&loan->l_duedate));
     } else
 	pr(" ** In Arrears **\n");