use Data::Peek;
my %d;
while (<DATA>) {
    s/^\s*>?\s*(.*?)[\s\r\n]*\z/$1/;
    m/^(\d+)$/ ? push @{$d{$a}} => $1 : ($a = $_);
    }
DDumper \%d;

__END__
>James
>40 
>James
>35
>James
>26
>James
>15
James
10
>12
>Philip
10
4
>5
Philip
James
Philip
18