The requirement is 10 TCHs per year, and you earn 10 TCHs for passing the exam.
If the current renewal year is 2019 and you got your license in 2019, you earned 10 TCHs for passing the exam so you do not need additional hours.
If the current renewal year is 2019 and you got your license in 2018, you earned 10 TCHs for passing the exam so you only need 10 more TCHs.