The monthly profit in dollars for a small consulting firm can be modeled by the equation $y=-16.7 x^{3}-400 x^{2}+$ $6,367 x-7,000,$ where $x$ is the number of new clients acquired during that month. For tax purposes, the owner asks the manager to try to make the December profit as close as possible to $\$ 11,000 .$ How many new clients should the manager try bring in?