Please make it correct

Today, I ran into some translation problem from Korean to English in the office. I am not sure whether my translation makes sense or not. It would be appreciated if you correct my translation. My trnslation is below; 'On average M/S versus the competitors is over 10% for the last 3 years' Thanks in advance.

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Hi Wonmin,

I wrote you about this sentence before, but did not hear back from you.  If you still need help with this sentence, please let me know so that we can talk about it during class.

Thank you,
Neda