The results are reported of the quantized Hall and transverse resistivity measurements made on n-channel (100) inversion layers of Si-MOSFET devices at temperatures T = 1.6 to 0.5 K, magnetic fields H = 9.0 and 10.5 T for various excitation current densities. The Hall resistivity ϱ xy is found to be integral fractions of h e 2 in precision better than 0.2 ppm over the concentration of electrons ieH hc = 1 × 10 12 to 3 × 10 12/cm 2 ( i = 4, 8, 12) at the lowest temperatures. When the transverse resistivity ϱ xx is finite in the Hall plateau regions, the deviation in ϱ xy is roughly given by Δϱ xy ( i) = C· ϱ min xx ( i) where C ≌ −0.1. This result is two orders of magnitude as large as that expected from existing theories.