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had been in the business since is the most popular phrase on the web.

has been in the business since 11,590,000 results on the web	had been in the business since 18,500,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
The company has been in the nickel business since 1996, producing about 29000 MT of nickel in 2005, and is the 10th largest nickel producer in the world. You're the best thing that's happened to this business since... Been in the family business since I was 15. I signed the first new business since lucky strike left, It's been a big bump in business since it came out. I've been looking after this business since my father passed away. I've been in the business since I'm 16. It's serious business since 9/11, making fake IDs.	I've been looking after this business since my father passed away. odd years, and he was looking to get out. Been in the family business since I was 15. Stan had been in the business for 20 I've been in the business since I'm 16. some You're the best thing that's happened to this business since... It's serious business since 9/11, making fake IDs.

has been in the business since

11,590,000 results on the web

had been in the business since

18,500,000 results on the web

More popular!

The company has been in the nickel business since 1996, producing about 29000 MT of nickel in 2005, and is the 10th largest nickel producer in the world.
You're the best thing that's happened to this business since...
Been in the family business since I was 15.
I signed the first new business since lucky strike left,
It's been a big bump in business since it came out.
I've been looking after this business since my father passed away.
I've been in the business since I'm 16.
It's serious business since 9/11, making fake IDs.