LOS ANGELES (CBS) — Early estimates indicate a steep drop-off in box office revenue outside the U.S. following the earthquake in Japan.

International movie ticket sales plunged 60 percent last weekend from a year earlier, according to Standard & Poor’s Equity Research analyst Tuna Amobi.

Amobi notes that Japan is one of Hollywood’s biggest markets, accounting for about 10 percent of international box office revenue. However, there were likely other factors in the weekend box-office decline.

After the earthquake and tsunami, studios are changing plans. Warner Entertainment Japan Inc. says theaters will stop showing Clint Eastwood’s movie “Hereafter,” which has scenes depicting the 2004 Indian Ocean tsunami.

Sony Pictures is delaying the release in Japan of “Battle: Los Angeles,” which is about an alien invasion in Southern California.

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