Compare words between two cells and get matching percentage

Hi all,

I have a column with 10,000+ lines, and lots of them are duplicated.
I have a formula that tells me how many times they are duplicated, but it only looks for 100% matching cells.

Now, lots of cells are partially duplicated, for example:

A1 - Team Abcde
A2 - Team Abcde Fghi
B1 - Team Abc

I would like to have a formula giving me a percentage of how two cells are similar to each others by checking the words.
In this case, B1 is 50% similar to A1 because only the word 'Team' is duplicated.
B1 is only 33,34% similar to A2.

I hope any of you can give me a hand on this, thanks :-)