Reality TV guru Mark Burnett is encouraged by the improved Week 2 ratings for his new series Shark Tank on ABC.

"How I'm judging it is the 18-49s, but what was important to me about (Sunday) was it really grew from its (Who Wants to be a) Millionaire? lead-in," Burnett told Sun Media. "And even though There Goes the Neighborhood on CBS had a bigger lead-in, we beat it. They dropped substantially and we went up substantially.

"I thought this would happen. The same in Canada, Dragons' Den (on CBC) took a while to grow and find an audience. It's smart TV."

Shark Tank was the most-watched show in the U.S. in the Sunday 9 p.m. hour last weekend, building by 1.5 million viewers (36%) from one week earlier (5.7 vs. 4.2 million).

"We didn't get what we thought would be a huge Millionaire lead-in, which was very soft," the British-born Burnett said. "So (last weekend) was key to us. We grew 30% from our lead-in, so it's a really good sign.

"I've had a hit on CBS, Survivor; a hit on NBC, The Apprentice; and Are You Smarter Than a 5th Grader? on Fox. So having a show that does really well on ABC is personally important for me."