Hello 1nickt,

You are right the year has 52 weeks and 1 or 2 day(s) depending upon the number of days in the year.

Sample of calculation on calendar common year 365 days:

1 common year = 365 days = (365 days) / (7 days/week) = 52.143 weeks =
+ 52 weeks + 1 day
[download]

Sample of calculation on leap year has 366 days, when February has 29 days:

1 leap year = 366 days = (366 days) / (7 days/week) = 52.286 weeks = 5
+2 weeks + 2 days
[download]

I was counting the remaining days as a week. So the solution is to remove the last input and count in total the remaining weeks:

Sample bellow before and after:

#!/usr/bin/perl
use strict;
use warnings;
use Date::Manip;
use Data::Dumper;

my ($start, $end) = qw(2017-01-01 2017-12-31);

# y:m:w:d:h:m:s
my @weeks = ParseRecur('0:0:1::0:0:0', $start, $start, $end);

print Dumper \@weeks;

=sample
$VAR1 = [
          '2017010100:00:00',
          '2017010800:00:00',
          '2017011500:00:00',
          '2017012200:00:00',
.
.
.
          '2017121700:00:00',
          '2017122400:00:00',
          '2017123100:00:00' # Not a week (remaining days)
        ];
=cut

pop @weeks;

say "Number of weeks: " . scalar @weeks;

print Dumper \@weeks;

=output
$VAR1 = [
          '2017010100:00:00',
          '2017010800:00:00',
          '2017011500:00:00',
          '2017012200:00:00',
.
.
.
          '2017121000:00:00',
          '2017121700:00:00',
          '2017122400:00:00' # Last week on 2017
        ];
=cut
[download]

BR / Thanos