Table 1. Annual Electricity Consumption Percentiles by Year Constructed, 1997
(kilowatthours per household)

  5th percentile 10th percentile 25th percentile   median   75th percentile 90th percentile 95th percentile
All Households 2,287 3,167 5,056 8,370 13,485 19,866 24,436
Year Constructed  
Before 1940 1,778 2,369 3,867 6,363 10,256 14,369 18,355
1940 to 1949 1,778 2,212 3,574 5,940 9,660 14,945 19,452
1950 to 1959 2,345 3,070 4,651 7,556 11,234 17,193 22,229
1960 to 1969 2,374 3,172 4,912 7,969 12,032 18,267 21,976
1970 to 1979 2,311 3,336 5,925 10,039 15,976 23,422 27,933
1980 to 1989 3,723 4,738 7,156 10,950 16,555 22,312 26,137
1990 to 1997 3,518 4,283 7,281 10,815 16,860 21,812 24,893
Graph of data

Notes: The data in this table are for households that used electricity.
The percentiles describe the distribution of household electricity consumption data; for example, 25% of households in units constructed before 1940 consumed less than 3,867 kWh and 75% consumed more than that amount.
Source: 1997 Residential Energy Consumption Survey.

Return to: “Median Values and Percentiles for Household Energy Data”
 

Table 2. Mean Annual Electricity Consumption by Year Constructed, 1997
(kilowatthours per household)

  Electricity Consumption per Household
(kWh)
Relative Standard Error (percent) Standard Error (kWh) 95% confidence level lower bound (kWh) 95% confidence level upper bound (kWh)
All Households 10,219 1.4 430 9,939 10,499
Year Constructed
Before 1940 7,781 2.6 202 7,384 8,177
1940 to 1949 7,641 4.8 367 6,922 8,359
1950 to 1959 9,033 3.0 271 8,502 9,564
1960 to 1969 9,459 3.1 293 8,884 10,034
1970 to 1979 11,976 2.9 347 11,295 12,657
1980 to 1989 12,449 2.6 324 11,814 13,083
1990 to 1997 12,512 4.4 551 11,433 13,591
Graph of data

Notes: The data in this table are for households that used electricity.
The standard error is a measure of sampling error and can be used to calculate a confidence range. For example, the estimate for electricity consumption in units constructed before 1940 is 7,781 kilowatthours (kWh) and the standard error is 202 kWh. The 95% confidence interval is calculated by multiplying 1.96 times the standard error, and the 95% confidence range is 7,384 kWh to 8,177 kWh.
Source: 1997 Residential Energy Consumption Survey.

Return to: “Median Values and Percentiles for Household Energy Data”