I verified using Excel and Oracle since the question states between I believe both the dates will not included in the calculation, so: 09/09/09 - 08/08/08 = 396 days (excluding 09/09/09 and 08/08/08) 10/10/10 - 09/09/09 = 395 days (excluding 09/09/09 and 10/10/10) so, a total of 791 days