Count last 10 occurrences of a word in a variable range

Please, I need an array formula to count how many times ""CAN" appears in the last 10(AD3) words in column G, until the row of 30(AD2) in column A, without a helper column (G:G).

I must keep cells AD2 and AD3 (or 2 others) as references.

I've tried with a helper colum, but it's too heavy to calculate, cause the actual sheet has thousands of rows and runs a macro.

See attached file.

Sorry, I couldn't attach a file by any way to the forum.
http://www.filedropper.com/canfiletoexcelforum

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Thanks to the unexpected and GREAT HELP of GC Excel, I adapted the solution he provided to get the actual working file, that is the attached file number 3.

Thank you again, FDibbins, for your attention.

Thank you VERY, VERY MUCH, GC Excel!