The impact of parameter variations in integrated analog circuits is usually analyzed by Monte Carlo methods with a high number of simulation runs. Few approaches based on interval arithmetic were not successful due to tremendous overapproximations. In this paper, we describe an innovative approach computing transient and DC simulations of nonlinear analog circuits with symbolic range representations that keeps correlation information, and hence has a very limited overapproximation. The methods are based on affine and quadratic arithmetic. Ranges are represented by unique symbols so that linear correlation information is preserved. We demonstrate feasibility of the methods by simulation results using complex analog circuits.