question: In 2013 Buffett announced another donation to the foundation for how much
answer: In July 2013 , Buffet announced another donation of his company 's Class B , this time in the amount worth $ 2 billion
turker_answer: In 2013 Buffett announced another donation to the foundation for $ 2 billion .
rule-based: In 2013 Buffett announced another donation to the foundation in July 2013 , Buffet announced another donation of his company 's Class B , this time in the amount worth $ 2 billion