How to place partially initialized struct object into a vector?

I currently have struct where I initialize only two of three member. I purposefully do this since during the time of creation I am not sure what the value will be ( I actually am fine with it being just zero).

struct my_data {
    my_data(int x_, int y_) {
       x = x_;
       y = y_;
    }


    int x;
    int y;
    double z = 0;
};

int main() {
   std::vector<my_data> my_vec;
   my_vec.resize(10);

}

When I do this I get error: no matching function for call .... _T1(std::forward<Args ..

Is there any way to avoid this error or should I have to include z also in as parameter in constructor.