You are looping over @ECL_STAT 2*1200 times! Loop over it once, storing the data in a structure that is efficient to look up by $NETID: 

for(  @ECL_STAT  ) {
    my( $NETID )= split /\|/, $_;
    push @{$byID{$NETID}}, $_;
}

[download]

Then you can do your calculations on that.

Update: Change 4 to 2. Thanks to arturo for the sharp eyes.

        - tye (but my friends call me "Tye")

In reply to (tye)Re: Grep Effeciency by tye
in thread Grep Effeciency by ImpalaSS

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