Comparison of the international sunspot index R_i with the American sunspot number R_A produced by the AAVSO since 1945. Top panel: monthly R_i and R_A values (black and white dots respectively) and 1-year smoothed average R_i and R_A values (red and blue curves respectively). The cycle numbers are indicated. Bottom panel: monthly ratios R_i = R_A (diamonds) and the 1-year smoothed ratio (solid line) with the 3σ confidence levels (dashed lines).