Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
What is 2006 when 1997 is 6.8?

### Inputs:
table_name: table, columns: ['Greek national account', '1970', '1980', '1990', '1995', '1996', '1997', '1998', '1999', '2000', '2001 1', '2002', '2003', '2004', '2005', '2006', '2007', '2008', '2009', '2010', '2011', '2012', '2013 2', '2014 2', '2015 3']

### Response:
SELECT 2006 FROM table WHERE 1997 = 6.8