World Series: A CBS Grand Slam : Television: The exciting finale Sunday was the week’s most-watched program. Viewership is the highest since 1987.

The length and dramatics of the seven-game World Series boosted CBS’ ratings 15% over last year’s four-game matchup, with the additional three games bringing the network between $30 million and $36 million in added advertising revenue, CBS Sports spokeswoman Susan Kerr said Tuesday.

The network’s coverage of the Minnesota Twins-Atlanta Braves baseball championship averaged a 24 rating over the course of the seven games, meaning each contest was seen in an average of about 22 million households, according to figures released Tuesday by the A. C. Nielsen Co. (Each ratings point is equivalent to 921,000 households.)

“Obviously, the nation was captured by this series, and this (rating) indicates the strong interest around the nation,” Kerr said. “We had some bad luck last year for sure, but it was great we had a seven-game series and everybody felt good about it.”

Last season, the Cincinnati Reds’ four-game sweep of the Oakland Athletics averaged a 20.8 rating, the second-lowest ever for a World Series, leading only Oakland’s four-game, earthquake-interrupted defeat of the San Francisco Giants the year before.

The 24 rating average was the highest since the 1987 World Series, which also saw Minnesota win in the maximum seven games. However, it trailed the three other seven-game series of the past decade: 1986 (28.6), 1985 (25.3) and 1982 (27.9).

Reasons for the slippage include the growth of cable networks, independent stations and the birth and rise of the Fox network.

Kerr contended that such comparisons aren’t meaningful.

“It’s not comparing apples and apples,” she said. “TV was a different animal then and there were different TV viewership habits.”

Since CBS became the sole home for post-season baseball in 1990, NBC and ABC have aggressively counterprogrammed baseball with made-for-TV movies and miniseries geared to female viewers. From 1976 to 1989, ABC and NBC had shared the post-season coverage. One network would get the league championship series, and the other the World Series, with the pattern alternating each year.

Neither network trotted out expensive counterprogramming, because any decline in the baseball ratings would impact on the network the following year when it would sell advertising based on the previous year’s ratings.

Minnesota’s 10-inning, series-clinching 1-0 victory Sunday was the week’s most-watched program, drawing a 32.2 rating and 49% of the available audience. It was the highest-rated series game since the final game of the 1987 series, which drew a 32.6 rating and a 50 share.