Derek, a cash basis, unmarried taxpayer, had $610 of state income tax withheld during 2017. Also in 2017, Derek paid $50 that was due when he filed his 2016 state income tax return and made estimated payments of $100 toward his 2017 state income tax liability. When Derek files his 2017 Federal income tax return in April 2018, he elects to take the standard deduction, which reduced his taxable income. As a result of overpaying his 2017 state income tax, Derek receives a refund of $435 early in 2018. How much of the $435 will Derek include in his 2018 gross income?