I know this is old, but the @value_array in the for-loop doesn't need to be created.

I'm sure there's a lot more that could be cleaned up to make this closer to a one-liner (just looking at it), but I figured I'd update the most important part, due to efficiency issues with creating temporary variables in a loop.

You can just reference an array's value like: $new_hash{$key}[0]

Note: The example uses $_ instead of $key and instead of choosing the second element in the array (1), I've replaced with the first element (0).