+=item increment_months_used
+
+Increments months_used by the given parameter
+
+=cut
+
+sub increment_months_used {
+ my( $self, $used ) = @_;
+ #UPDATE cust_pkg_discount SET months_used = months_used + ?
+ #leaves no history, and billing is mutexed per-customer, so the dum way is ok
+ $self->months_used( $self->months_used + $used );
+ $self->replace();
+}
+