ozo,Average!

The $b variable is from the Infile,this statement: runt1!9!14(The 2nd value,it can be 3values or 5values or 9values)
Infile:
runt1!9!14
runt2!9!14
runt3!9!15
runt4!9!25
runt5!9!3


Then How do i calculate my average of the values for each parameter and print the average value to the end of each line(See output file) in the output file e.g
-9.960116E+02!+1.002406E-03!
means that -9.960116 is to the power of 2,1.002406 is to the power of -3.

ps:Your codes did not include this calculation of the power to 3?It only sum up the total is it?

Output file(Contains only 2values but it can be 3 or 5 or 9 values):

s1!NE2 40/40 Vth0!+9.939227E+02!+9.982348E+02!avg(value calculated)!
s2!NE2 40/40 Vth0!-9.960116E+02!+1.002406E-03!avg(value calculated)!    

s1!Vth Vb/2.5!+3.985872E-08!+3.948130E-08!avg(value calculated)!
s2!Vth Vb/2.5!+3.974027E-08!+3.971276E-08!avg(value calculated)!


Below is my codes:
open(FILE1,"infile") || die "Can't open infile because $!";
open(FILE2,">outfile") || die "Can't open outfile because $!";

while( <FILE1> )
{
  ($a,$b,$c) = split(/!/);
  $c = sprintf("%02d",$c);
  open (FILE3,"<$a") || die "Can't open $a because $!";
  while( <FILE3> )
  {
    next unless /SYS_WAFERID!$c\b/.../SYS_WAFERID!$c\b/;
    next unless ($para,@values) = (/([^!]+)!.*!/,/!([-+][-+\d.E]+)/g);
    push @para,$para unless $para{$para};
    if($b == 3)
    {
      for('s1'..'s3')
      {
         push @{$para{$para}{$_}},shift @values;
      }
    }
    if($b == 5)
    {
      for('s1'..'s5')
      {
         push @{$para{$para}{$_}},shift @values;
      }
    }
    if($b == 9)
    {
      for('s1'..'s9')
      {
         push @{$para{$para}{$_}},shift @values;
      }
    }
  }
  close FILE3;
}
for $p ( @para )
{
  if($b == 3)
  {
    for $s ('s1'..'s3' )
    {
       print FILE2 join"!",$s,$p,@{$para{$p}{$s}};
       $avg =0;
       for(@{$para{$p}{s}})
       {
          $avg = $avg + $_;
       }
       $avg/=@{$para{$p}{$s}};
       print FILE2 "!$avg!\n";
       #print FILE2 "\n";
    }
    print FILE2 "\n";
  }
  if($b == 5)
  {
    for $s ('s1'..'s5' )
    {
        print FILE2 join"!",$s,$p,@{$para{$p}{$s}};
        print FILE2 "\n";
    }
    print FILE2 "\n";
  }
  if($b == 9)
  {
    for $s ('s1'..'s9' )
    {
        print FILE2 join"!",$s,$p,@{$para{$p}{$s}};
        print FILE2 "\n";
    }
    print FILE2 "\n";
  }
}

How do i solve my problem of getting !avg(0)!
Pls help,thanks!!