This may be one of the few cases where awk is the correct solution.

df -P | awk '/^\//{printf("%5s %s\n", $5, $6);}'
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df -P | perl -ne 'printf("%5s %s\n", (split(/\s+/, $_))[4, 5])'
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If you want to do a lot more formating; then I would write a complete perl program.

use Filesys::Statvfs;

open MOUNTED, "</proc/mounts" || die "Could not open /proc/mounted\n";

while (my $mountpoint = <MOUNTED>) {
    my ($bsize, $blocks, $bfree, $bavail, $files, $ffree, $namelen);
    my $path = (split(/\s+/, $mountpoint))[1];
if (1) {
    ($ftype, $bsize, $blocks, $bfree, $files,
     $ffree, $bavail) = statvfs("/tmp");
} else {  # This is not very portable
    my $buf = "\0"x64;
    syscall(99, $path, $buf) == 0 or die "Bad mountpoint $path\n";

    ($bsize, $blocks, $bfree, $bavail, $files, $ffree, $namelen)
        = unpack  "x4 L6 x8 L", $buf;

}
    next unless $blocks;

    print <<EOT;
                            path: $path
     Optimal transfer block size: $bsize
           Blocks in file system: $blocks
                     Blocks free: $bfree (${\(int $bfree/$blocks*100)}
+%)
           User blocks available: $bavail (${\(int $bavail/$blocks*100
+)}%)
                          Inodes: $files
                     Free inodes: $ffree (${\(int $ffree/$files*100)}%
+)
EOT
}
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