# work out end of current month
my ($y,$m,$d) = Today();
my $mth_end = sprintf "%04d,%02d,%02d",$y,$m,Days_in_Month($y,$m);
# ($year,$month,$day) = Add_Delta_Days($year,$month,$day,$Dd);
my $prev_mth_end = sprintf "%04d,%02d,%02d",
                   Add_Delta_Days($y,$m,1,-1);