user: Question: How many countries spent at least $51.0 billion in international tourism in 2012?
Columns: ['Rank 2012', 'Country', 'UNWTO Region', 'International tourism expenditure 2011', 'International tourism expenditure 2012', '% change']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'China', 'Asia', '$72.3 billion', '$102.0 billion', '40.5']
SQL:

assistant: SELECT COUNT("Rank 2012") FROM "Table" WHERE "International tourism expenditure 2011" = '$51.0 billion';