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After 10 years, Diane Sawyer is leaving ABC News' "Good Morning America."

The veteran newscaster announced on this morning's show that this will be her last week as co-anchor after more than 2,500 "Good Mornings."

"I've calculated -- 2,881 shows," she said. "Roughly."

The 63-year-old is primed to step behind the desk of the "World News" as the new anchor in January.

"I hope you celebrate with us this week, laugh with us this week," she added.