LOS ANGELES - "Transformers" robots have lost some of their money-making power but still have delivered the biggest opening weekend domestically so far this year. Distributor Paramount Pictures said Sunday that "Transformers: Dark of the Moon" took in $97.4 million domestically in its first weekend. That beat the $90.2 million debut of Disney's "Pirates of the Caribbean: On Stranger Tides." But the domestic haul for the sci-fi sequel was down from the $127.9 million first weekend for 2009's "Transformers: Revenge of the Fallen." Since opening Tuesday night, the new "Transformers" pulled in $162 million through Sunday, a drop from $200.1 million for "Revenge of the Fallen" in its first five days. Paramount estimates "Dark of the Moon" will hit $180.9 million domestically by the end of the long Fourth of July weekend Monday.