Thousands of rubber ducks are seen as they dropping into Chicago River within the 13th Windy City Rubber Ducky Derby to benefit Special Olympics Illinois in Chicago, the United States on August 9, 2018. Thousands of spectators watch over approximately 60,000 yellow rubber ducks splash into the Chicago River from the Columbus Drive bridge in downtown Chicago and race down river towards the finish line. (Photo/VCG)

Rubber ducks float down the Chicago River during the 13th Annual Chicago Ducky Derby in Chicago, the United States, Aug 9, 2018. (Photo/VCG)

Rubber ducks are dropped into the Chicago River during the 13th Annual Chicago Ducky Derby in Chicago, the United States, Aug 9, 2018. (Photo/VCG)

Rubber ducks float down the Chicago River during the 13th Annual Chicago Ducky Derby in Chicago, the United States, Aug 9, 2018. (Photo/VCG)

People attend the festival as thousands of rubber ducks dropped into Chicago River within the 13th Windy City Rubber Ducky Derby to benefit Special Olympics Illinois in Chicago, the United States on August 9, 2018. (Photo/VCG)

Rubber ducks float down the Chicago River during the 13th Annual Chicago Ducky Derby in Chicago, the United States, Aug 9, 2018. (Photo/VCG)

Rubber ducks float down the Chicago River during the 13th Annual Chicago Ducky Derby in Chicago, the United States, Aug 9, 2018. (Photo: Xinhua)