Derek, a cash basis, unmarried taxpayer, had $610 of state income tax withheld during 2015. Also in 2015, Derek paid $50 that was due when he filed his 2014 state income tax return and made estimated payments of $100 towards his 2015 state income tax liability. When Derek files his 2015 Federal income tax return in April 2016, he elects to take the standard deduction, which reduced his taxable income. As a result of overpaying his 2015 state income tax, Derek receives a refund of $435 early in 2016. How much of the $435 will Derek include in his 2016 gross income?