# Use a sentinel variable

    my $first;
    foreach my $well (@derivative) {
        next unless $first++;
        # Do something
    }



    # Use an array slice

    foreach my $well (@derivative[1..$#derivative]) {
        # Do something
    }



    # Use the array indices

    foreach my $i (1..$#derivative) {
        my $well = $derivative[$i];
        # Do something
    }