While I must second the use of map and sprintf, you may be interested to know that rounding constitutes several Categorized Questions and Answers, is found in perlfaq4, and a fairly common question. In the interest of completness (and TimToady), there are other methods to round numbers as shown in a variety of threads (eg Re: Rounding function and Re^2: Splitting String???), which include the following:

int ($num + .5);

($num += 5 / (10 ** ($decimal_places + 1))) =~ s/(?<=\.)(\d{1,$decimal
+_places}).*$/$1/;
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In addition to Zaxo's use of map, you may also be interested in using $, (or $" if interpolated; see perlvar), and printing directly, eg:

$, = $/;
print map { sprintf("%.2f", $_) } values %stats;
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