do() returns the number of rows of data returned. If you want to get the actual value, you'll need to do: 
my $sth = $dbh->prepare("SELECT avg(...) FROM prospects");
$sth->execute;
my ($avg) = $sth->fetchrow_array;

[download]
There's probably a shorter way to do that though...

Update: shorter way: 

my ($avg) = $dbh->selectrow_array("SELECT avg(...) FROM prospects");

[download]
Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re: AVG returns COUNT by japhy
in thread AVG returns COUNT by DrAxeman

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