Though I didn't find such information on Ubuntu's documentation, I created a simple script to calculate it manually:
#!/bin/bashubuntu_main=$(lynx -dump http://archive.ubuntu.com/ubuntu/dists/focal/main/binary-amd64/Packages.gz | grep ^Package: | wc -l)ubuntu_universe=$(lynx -dump http://archive.ubuntu.com/ubuntu/dists/focal/universe/binary-amd64/Packages.gz | grep ^Package: | wc -l)ubuntu_restricted=$(lynx -dump http://archive.ubuntu.com/ubuntu/dists/focal/restricted/binary-amd64/Packages.gz | grep ^Package: | wc -l)ubuntu_multiverse=$(lynx -dump http://archive.ubuntu.com/ubuntu/dists/focal/multiverse/binary-amd64/Packages.gz | grep ^Package: | wc -l)percentage="($ubuntu_restricted+$ubuntu_multiverse)/($ubuntu_main+$ubuntu_universe)"echo "Total number of packages on Ubuntu's main repository = $ubuntu_main"echo "Total number of packages on Ubuntu's universe repository = $ubuntu_universe"echo "Total number of packages on Ubuntu's restricted repository = $ubuntu_restricted"echo "Total number of packages on Ubuntu's multivrese repository = $ubuntu_multiverse"echo "Percentage of non-free packages on Ubuntu's repositories= $(echo $percentage*100 | bc -l) %"Output:
$ ./sample Total Packages on Ubuntu's main repository = 6090Total number of packages on Ubuntu's universe repository = 53206Total number of packages on Ubuntu's restricted repository = 143Total number of packages on Ubuntu's multivrese repository = 813Percentage of non-free packages = 1.61225040474905558500 %For Debian GNU/Linux:
$ cat sample #!/bin/bashdebian_main=$(lynx -dump http://ftp.debian.org/debian/dists/buster/main/binary-amd64/Packages.gz | grep ^Package: | wc -l)debian_contrib=$(lynx -dump http://ftp.debian.org/debian/dists/buster/contrib/binary-amd64/Packages.gz | grep ^Package: | wc -l)debian_nonfree=$(lynx -dump http://ftp.debian.org/debian/dists/buster/non-free/binary-amd64/Packages.gz | grep ^Package: | wc -l)percentage="($debian_contrib+$debian_nonfree)/($debian_main)"echo "Total number of packages on Debian's main repository = $debian_main"echo "Total number of packages on Debian's contrib repository = $debian_contrib"echo "Total number of packages on Debian's non-free repository = $debian_nonfree"echo "Percentage of non-free packages on Debian GNU/Linux = $(echo $percentage*100 | bc -l) %"$ ./sample Total number of packages on Debian's main repository = 56873Total number of packages on Debian's contrib repository = 293Total number of packages on Debian's non-free repository = 602Percentage of non-free packages on Debian GNU/Linux = 1.57368171188437395600 %Note: update and backport repositories are not considered for this analysis