Not to quarrel because your explanation of the regex problems is exemplary, but OP is clearly dealing with a multi-line logfile, in which some lines begin with ~|TOTAL. Hence, an array better matches the SOPW spec than the string is your "Test Case."

Aside to Bindo: Your spec comes up a little short of perfection because (very strictly speaking and very nitpicky) there's no requirement -- merely a single illustration -- that what's captured be numeric followed by a percent sign. What if the notation were hex, binary or some sort of non-Arabic numbers? In any case, I've treated you spec as "any line that begins with tilde, pipe, 'TOTAL' followed by anything" which is the only reason my regex differs from RMGir's:

#!/usr/bin/perl
use 5.016;
use warnings;

#1061986 

my @logfile = ("~|TOTAL 24.1% 0.4%", 
                "~|not a total 11%", 
                "~|TOTAL 21.0% 0.7%", 
                "FOOBAR", 
                "~|TOTAL 13.7% 10.2%",
                "~|TOTAL last5 6",
              );
my @FIGURE;

for my $logentry(@logfile) {
    if ($logentry =~ /~\|(TOTAL.*)/ ) {
        push @FIGURE, $1;
    } else {
        say "\t \$logentry, $logentry, does not match pattern";
    }
}

for (@FIGURE) {
    say $_;
}

=head execution:

C:\>1061986.pl
         $logentry, ~|not a total 11%, does not match pattern
         $logentry, FOOBAR, does not match pattern
TOTAL 24.1% 0.4%
TOTAL 21.0% 0.7%
TOTAL 13.7% 10.2%
TOTAL last5 6

=cut

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In reply to Re^2: Extracting string from a file by ww
in thread Extracting string from a file by Bindo

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