inserting grep -c value into an email subject

I am profoundly new to *nix, but had a project dropped in my lap that has sparked an interest, leading me here.

I was tasked with daily sending one of our customers a listing of all the spam our filter blocked that was heading for them.
Between Google and I;
I discovered the Server is running Linux version 2.6.11-gentoo-r4.
I learned the basics of grep enough to pare down the amavis.log file to only the pertinent data and figured out how to get it mailed out.
I added a crontab to do this daily, and the job was done to the customer's satisfaction.

Unfortunately, I cannot leave well enough alone, and decided I wanted to have the email subject include the total blocked messages.
grep -c Blocked gives me the total, but I have not been able to track down how to modify the mail subject to reflect this.
I attempted to assign n = grep -c Blocked /var/amavis/amavis.log, but $n just echos as grep.

Pointing out where I'm screwing up or directing me to a link where I can find the info would be greatly appreciated.

n=`grep -c Blocked /var/amavis/amavis.log`

Just for an FYI, those are back ticks, and not single quotes. This is on the same key as ~.

That makes a huge difference, thank you!

So far, I have used email -s "customer spam report" customer@address.sam to deliver the resulting log, which works.

My goal is to insert my newly created $n value into the subject, ala' "Customer Spam Report ($n messages)".