+=item seconds_since TIMESTAMP
+
+Returns the number of seconds all accounts (see L<FS::svc_acct>) in this
+package have been online since TIMESTAMP.
+
+TIMESTAMP is specified as a UNIX timestamp; see L<perlfunc/"time">. Also see
+L<Time::Local> and L<Date::Parse> for conversion functions.
+
+=cut
+
+sub seconds_since {
+ my($self, $since) = @_;
+ my $seconds = 0;
+
+ foreach my $cust_svc (
+ grep { $_->part_svc->svcdb eq 'svc_acct' } $self->cust_svc
+ ) {
+ $seconds += $cust_svc->seconds_since($since);
+ }
+
+ $seconds;
+
+}
+