Generally, here on perlmonks, it's a good idea to show your code. We're all more inclined to help you if you show what you've been doing, to prove that you've done your homework. In this vein, here are a couple of links:

• How to RTFM: A good explanation of how to do a little research
• http://perldoc.com: The docs should always be where you go first.

But, as long as you took the time to post the question, here is one of the many ways you might do it.

foreach $item (@data) {
    $members{$item}++;
}
foreach $item (keys %members) {
    print "$item : $members{$item}";
}
[download]

Light a man a fire, he's warm for a day. Catch a man on fire, and he's warm for the rest of his life. - Terry Pratchet

my @array = ('foo', 'foo', 'bar', 'foo', 'bar', 'baz');
my %count;
$count{$_}++ for @array;

for(sort(keys(%count))) { 
    print "$_: $count{$_}\n";
}
[download]

I'm sure you can work out how to then calculate the percentages.

my @data = &initialize_it_the_way_you_want() ;

my $total = @data ; # or scalar @data, explicitly
die "give me arguments!" unless $total ;

my %count ;
my %perc ;
map $count{$_}++,@data ;
map { $perc{$_} = $count{$_}/$total } keys %count ;

# Now you have recurrence counts on %count and
# percentages on %perc to do whatever you want.
[download]

Ciao!
--bronto

# Another Perl edition of a song:
# The End, by The Beatles
END {
  $you->take($love) eq $you->made($love) ;
}