Author's headline comparison is the decline in own-price responsiveness from the pre-crisis 1962-72 whole-subperiod to the 1973-75 subperiod; Table I (average price) results are presented and discussed first and most prominently || 'the electricity price coefficients (b1) for the three-year regressions range from -1.119 to -1.050, with a coefficient of -1.075 for the entire 1962-72 subperiod... The corresponding electricity price coefficient for the 1973-75 period is -0.570' (p.109)
Yang, Y.L. (1978): “Temporal Stability of Residential Electricity Demand in the United States.” Southern Economic Journal 45(1), 107-115