Improving on your idea:
print scalar grep{$_->{'age'} == 12} values %hoh;

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CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

In reply to Re^2: Find number of unique values in hash by CountZero
in thread Find number of unique values in hash by rethaew

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