Table 6. Stability of inter-party competition (Z-score)

Country Mean electoral volatility Cumulative electoral volatility Mean Z-score
President Parliament President Parliament
USA 1.62 1.85 1.23 1.78 1.62
Uruguay 1.41 1.04 1.03 1.17 1.16
Mexico 0.87 0.65 1.21 0.66 0.85
El Salvador 0.96 1.01 0.97 0.26 0.80
Chile 0.16 0.86 0.92 1.20 0.79
Honduras 1.26 0.88 0.40 0.33 0.72
Dominican Republic 0.63 0.32 0.38 0.78 0.53
Brazil 0.07 0.65 0.52 0.49 0.43
Paraguay -0.68 -0.08 1.03 1.02 0.32
Russia 0.91 -0.09 0.75 -0.35 0.31
Costa Rica 0.91 0.42 -0.38 -0.38 0.14
Panama -0.82 0.26 0.39 0.10 -0.02
Nicaragua 0.01 -0.57 0.02 -0.18 -0.18
Colombia -0.52 -0.41 -1.18 -0.37 -0.62
Argentina -1.11 -0.32 -0.71
Ecuador -0.91 -0.55 -1.57 -1.04 -1.02
Peru -1.70 -1.93 -0.79 -0.32 -1.18
Venezuela -0.64 -1.56 -1.61 -1.68 -1.37
Bolivia -0.80 -1.37 -1.60 -1.79 -1.39
Guatemala -1.63 -1.38 -1.39 -1.70 -1.52