8-F-i

APPENDIX 8-F. DEVELOPMENT OF MONTHLY ALLOCATION FACTORS FOR 

RESIDENTIAL BASELINE ENERGY USE

TABLE OF CONTENTS

8-F.1 INTRODUCTION .................................................................................................. 8-F-1

8-F.2 METHODOLOGY ................................................................................................. 8-F-1

LIST OF TABLES

Table 8-F.2.1 Fraction of RECS 2001 Records With Monthly Billing Data By 

Census Division .......................................................................................... 8-F-1

Table 8-F.2.2 Monthly Allocation Factors By Census Division (CD), Large State 

(LS), Space Heating Fuel Type (EH) and Water Heating Fuel Type 

(EWH). ........................................................................................................ 8-F-2
8-F-1

APPENDIX 8-F. DEVELOPMENT OF MONTHLY ALLOCATION FACTORS 

FOR RESIDENTIAL BASELINE ENERGY USE

8-F.1 INTRODUCTION

 Utility bills for residential consumers frequently include block rates and/or seasonal rates 

for electricity use. For tariffs with block rates, the unit price per kilowatt-hour (kWh) varies 

according to how much electricity the consumer uses during the billing period. For tariffs with 

seasonal rates, these unit prices differ in summer and winter months, with the assignment of 

months to a particular season varying by utility. To correctly calculate marginal prices for this 

type of tariff, an estimation of a residential household’s monthly baseline electricity consumption 

is required. This appendix describes the methodology used to make this estimation. 

8-F.2 METHODOLOGY

 The approach uses the monthly household billing data available for the RECS 2001 

survey year to develop monthly allocation factors that define the fraction of annual energy use 

that occurs in each month.1

 The RECS 2001 survey included the collection of monthly electricity 

consumption and expenditure data for a large fraction of the total household sample. For this 

analysis, a minimum of eight bills for a calendar year, with a minimum of three for each season, 

were required for a record to be included in the data set. This results in monthly billing data for 

approximately 70–75 percent of all households by weight, as shown in Table 8-F.2.1. 

Table 8-F.2.1 Fraction of RECS 2001 Records With Monthly Billing Data By Census 

Division

Census 

Division

All Records Records with Bills

N N % by Weight

1 396 279 71%

2 691 482 69%

3 681 522 76%

4 366 269 72%

5 626 469 75%

6 409 289 70%

7 454 349 75%

8 407 310 76%

9 792 566 70%

Nation 4822 3535 73%

The billing periods for each RECS household are approximately one month long, but 

with varying start and end dates. The data were interpolated onto calendar months by (1) 

calculating the average daily electricity use during each billing period and (2) defining a total 
8-F-2

electricity use for the calendar month as the sum of the daily values. In cases where a household 

is missing one or more bills, the daily values for the missing periods were estimated as an 

average of the daily values for the preceding and following periods. This procedure leads to a set 

of twelve monthly electricity consumption values for 3535 of the RECS 2001 records. The 

percent of annual energy use that occurs in each month, which we call the monthly allocation 

factor, is then easily calculated for each household. 

 From this set, those RECS households having room air conditioners and with non-zero 

annual cooling energy use were chosen to represent the consumer population impacted by the 

current rulemaking. For these consumers, the monthly variability in electricity consumption 

depends primarily on three factors: geographic region (which incorporates both climate and 

building codes), the type of fuel used for space heating and the fuel used for water heating. 

Accordingly, the records were grouped according to four categorical variables: the two 

geographic variables Census Division (CD) and Large State (LS), a flag (1/0) for electric versus

other space heating (EH in Table 8-F.2.2), and a flag (1/0) for electric versus other water heating 

(EWH in Table 8-F.2.2). For each category, weighted-average monthly allocation factor were 

calculated as a weighted sum over all households in that category, using the RECS “NWEIGHT” 

variable as the weight. Some categories in Census Division 2 did not contain enough records to 

calculate a weighted average. In these cases, the number of categories was reduced by dropping 

the water-heating flag, and the weighted averages calculated for the broader category. The 

resulting set of categories and allocation factors are presented in Table 8-F.2.2. 

Table 8-F.2.2 Monthly Allocation Factors By Census Division (CD), Large State (LS), 

Space Heating Fuel Type (EH) and Water Heating Fuel Type (EWH).

CD LS EH EWH Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

1 0 0 0 0.086 0.075 0.078 0.071 0.074 0.088 0.100 0.102 0.080 0.079 0.080 0.089

1 0 0 1 0.091 0.080 0.089 0.080 0.079 0.079 0.085 0.085 0.075 0.080 0.084 0.093

1 0 1 0 0.085 0.067 0.063 0.071 0.064 0.087 0.132 0.122 0.078 0.067 0.075 0.088

1 0 1 1 0.131 0.116 0.118 0.074 0.054 0.049 0.056 0.053 0.057 0.069 0.094 0.128

2 0 0 0 0.087 0.073 0.077 0.070 0.074 0.092 0.111 0.113 0.080 0.073 0.072 0.081

2 0 0 1 0.087 0.078 0.081 0.076 0.080 0.087 0.102 0.101 0.076 0.071 0.075 0.087

2 0 1 n/a 0.114 0.099 0.108 0.095 0.070 0.062 0.073 0.067 0.060 0.067 0.075 0.110

2 1 0 0 0.082 0.069 0.076 0.069 0.077 0.089 0.110 0.112 0.087 0.074 0.075 0.080

2 1 0 1 0.090 0.084 0.078 0.070 0.079 0.091 0.094 0.090 0.070 0.081 0.083 0.090

2 1 1 n/a 0.125 0.089 0.086 0.087 0.074 0.062 0.065 0.082 0.066 0.069 0.075 0.120

3 0 0 0 0.083 0.071 0.074 0.067 0.074 0.093 0.121 0.109 0.076 0.071 0.076 0.086

3 0 0 1 0.090 0.079 0.082 0.073 0.072 0.081 0.106 0.098 0.079 0.077 0.078 0.087

3 0 1 0 0.114 0.102 0.084 0.054 0.048 0.081 0.127 0.102 0.069 0.064 0.069 0.085

3 0 1 1 0.120 0.101 0.095 0.064 0.058 0.069 0.094 0.083 0.062 0.063 0.078 0.115

4 0 0 0 0.086 0.072 0.070 0.064 0.072 0.093 0.130 0.109 0.074 0.066 0.077 0.088

4 0 0 1 0.086 0.082 0.077 0.069 0.067 0.087 0.103 0.092 0.073 0.080 0.090 0.095

4 0 1 0 0.132 0.112 0.109 0.068 0.051 0.053 0.063 0.060 0.044 0.056 0.112 0.140

4 0 1 1 0.132 0.112 0.109 0.068 0.051 0.053 0.063 0.060 0.044 0.056 0.112 0.140

5 0 0 0 0.077 0.064 0.074 0.073 0.078 0.094 0.115 0.119 0.087 0.069 0.073 0.077

5 0 0 1 0.082 0.073 0.080 0.072 0.077 0.092 0.107 0.110 0.085 0.071 0.071 0.080

5 0 1 0 0.071 0.057 0.068 0.077 0.092 0.107 0.126 0.113 0.086 0.066 0.066 0.071

5 0 1 1 0.124 0.094 0.093 0.062 0.060 0.073 0.085 0.081 0.061 0.060 0.078 0.128
8-F-3

5 4 0 0 0.053 0.049 0.064 0.072 0.088 0.121 0.124 0.124 0.107 0.072 0.064 0.064

5 4 0 1 0.123 0.085 0.047 0.045 0.050 0.062 0.089 0.110 0.100 0.087 0.084 0.117

5 4 1 0 0.098 0.063 0.076 0.076 0.074 0.093 0.097 0.091 0.078 0.071 0.084 0.098

5 4 1 1 0.081 0.064 0.071 0.075 0.085 0.094 0.098 0.104 0.094 0.081 0.072 0.082

6 0 0 0 0.070 0.056 0.061 0.065 0.082 0.105 0.134 0.132 0.091 0.066 0.064 0.074

6 0 0 1 0.086 0.072 0.075 0.069 0.077 0.089 0.109 0.108 0.085 0.072 0.075 0.083

6 0 1 0 0.127 0.093 0.090 0.063 0.057 0.068 0.083 0.078 0.065 0.070 0.085 0.121

6 0 1 1 0.127 0.093 0.090 0.063 0.057 0.068 0.083 0.078 0.065 0.070 0.085 0.121

7 0 0 0 0.058 0.050 0.056 0.061 0.083 0.113 0.156 0.145 0.096 0.062 0.059 0.060

7 0 0 1 0.063 0.053 0.061 0.074 0.092 0.109 0.151 0.122 0.086 0.067 0.059 0.063

7 0 1 0 0.114 0.087 0.081 0.058 0.056 0.067 0.101 0.119 0.088 0.071 0.069 0.091

7 0 1 1 0.105 0.090 0.064 0.055 0.063 0.078 0.092 0.099 0.080 0.070 0.078 0.129

7 3 0 0 0.063 0.054 0.057 0.057 0.084 0.114 0.148 0.140 0.095 0.064 0.058 0.065

7 3 0 1 0.103 0.096 0.073 0.057 0.067 0.083 0.120 0.097 0.066 0.070 0.077 0.092

7 3 1 0 0.063 0.048 0.049 0.060 0.086 0.117 0.151 0.147 0.095 0.061 0.054 0.069

7 3 1 1 0.054 0.048 0.054 0.062 0.110 0.107 0.124 0.124 0.099 0.072 0.061 0.086

8 0 0 0 0.085 0.076 0.077 0.071 0.080 0.091 0.106 0.093 0.074 0.078 0.080 0.091

8 0 0 1 0.093 0.078 0.079 0.070 0.072 0.075 0.090 0.086 0.079 0.087 0.095 0.097

8 0 1 0 0.083 0.076 0.090 0.081 0.061 0.078 0.106 0.099 0.076 0.072 0.087 0.091

8 0 1 1 0.127 0.100 0.089 0.062 0.054 0.067 0.075 0.067 0.053 0.062 0.114 0.130

9 0 0 0 0.086 0.074 0.076 0.068 0.073 0.082 0.093 0.094 0.084 0.084 0.087 0.099

9 0 0 1 0.083 0.076 0.085 0.079 0.079 0.082 0.091 0.093 0.087 0.084 0.078 0.083

9 0 1 0 0.126 0.105 0.094 0.075 0.055 0.058 0.067 0.053 0.056 0.089 0.101 0.124

9 0 1 1 0.126 0.105 0.094 0.075 0.055 0.058 0.067 0.053 0.056 0.089 0.101 0.124

9 2 0 0 0.084 0.073 0.078 0.075 0.083 0.091 0.092 0.094 0.085 0.079 0.081 0.087

9 2 0 1 0.106 0.082 0.084 0.082 0.076 0.079 0.070 0.074 0.072 0.074 0.097 0.103

9 2 1 0 0.085 0.076 0.071 0.074 0.084 0.077 0.090 0.083 0.089 0.098 0.085 0.088

9 2 1 1 0.117 0.091 0.070 0.048 0.058 0.085 0.106 0.091 0.059 0.060 0.097 0.117
8-F-4

REFERENCES

1. U.S. Department of Energy - Energy Information Administration, RECS 2001 Billing 

Data, 2001. (Last accessed March, 2005.) Data provided electronically to LBNL.