Redesign Options for the Consumer 

Expenditure Survey 

Nancy Mathiowetz, University of Wisconsin-Milwaukee 

Kristen Olson, University of Nebraska-Lincoln 

Courtney Kennedy, Abt SRBI 

October 26, 2011 

Prepared for: 

National Academy of Sciences 

NAS Solicitation Number DBASSE-004950-0001-031411
2 

Understanding the Problem 

 Disparity between CE and Benchmarks 

 Measurement error 

 Nonresponse error 

 Both 

 Changes in the Survey and Consumer Environment 

 Use of technology in data collection 

 E-commerce; big box shopping 

 Flexible, Responsive Design 

 Ecological validity: one size does not fit all 

 Mode, number of diaries, technology 
New Design: Overview 

 Sample Design 

 Cross-sectional and panel components 

 Questionnaire 

 In person interview with four week diary 

 Tablet computer + scanner + barcode reader 

 Flexible memory ‘triggers’ 

 Alternative Data Sources 

 Federal and nonfederal sources 

 Nonresponse 

 Active monitoring 

 Responsive ‘end-stage’ design 

 Costs 

3 
4 

Study Design 

 Cross-sectional component 

 Initial interview 

 Diary: One month of data collection 

 Wrap up interview 

 N=7000 completes per quarter 

 Panel component 

 Three points in time, administered at six month intervals 

 Same design as cross sectional component 

 Initial Interview 

 One Month Diary 

 Wrap up Interview 

 N=450 completes per quarter per wave 

 Total number of interviews 

 8350 completes per quarter 

 8350*4 = 33400 completes per year 

 Increase over the current design 
5 

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Cross-sectional Component

Yr 1 samples

Yr 2 samples

Yr 3 samples

Panel Component

Yr 1 Jan Cohort 150 150 150

Yr 1 Feb Cohort 150 150 150

Yr 1 Mar Cohort 150 150 150

Yr 1 Apr Cohort 150 150 150

Yr 1 May Cohort 150 150 150

Yr 1 Jun Cohort 150 150 150

Yr 1 Jul Cohort 150 150 150

Yr 1 Aug Cohort 150 150 150

Yr 1 Sep Cohort 150 150 150

Yr 1 Oct Cohort 150 150 150

Yr 1 Nov Cohort 150 150 150

Yr 1 Dec Cohort 150 150 150

Yr 2 Jan Cohort 150 150 150

Yr 2 Feb Cohort 150 150 150

Yr 2 Mar Cohort 150 150 150

Yr 2 Apr Cohort 150 150 150

Yr 2 May Cohort 150 150 150

Yr 2 Jun Cohort 150 150 150

Yr 2 Jul Cohort 150 150 150

Yr 2 Aug Cohort 150 150 150

Yr 2 Sep Cohort 150 150 150

Yr 2 Oct Cohort 150 150 150

Yr 2 Nov Cohort 150 150 150

Yr 2 Dec Cohort 150 150 150

Yr 3 Jan Cohort 150 150

Yr 3 Feb Cohort 150 150

Yr 3 Mar Cohort 150 150

Yr 3 Apr Cohort 150 150

Yr 3 May Cohort 150 150

Yr 3 Jun Cohort 150 150

Yr 3 Jul Cohort 150

Yr 3 Aug Cohort 150

Yr 3 Sep Cohort 150

Yr 3 Oct Cohort 150

Yr 3 Nov Cohort 150

Yr 3 Dec Cohort 150

Total Interviews

Key

 1st interview

 2nd interview

 3rd interview

7,450 7,450 7,900 7,900 8,350 8,350 8,350 8,350 8,350 8,350 8,350 8,350

7,000 7,000 7,000 7,000

7,000 7,000 7,000 7,000

Year 1 Year 2 Year 3

7,000 7,000 7,000 7,000
Why a two-sample design? 

 Prospective data collection vs. retrospective recall 

 Primary goal: Minimize use of retrospective recall 

 Minimum requirement: 12 month change estimates for the same household 

 6 month interview allows additional information on a sample of households; less 

‘reteaching’ 

 Retrospective questions to ‘set the stage’ and diagnose potential nonresponse 

errors 

 Respondent burden 

 One or three interviews rather than five 

 Use all three interviews rather than throw away data 

 Outcome: lower attrition and panel conditioning 

 Micro-level analyses 

 Within-CU change over an entire month 

 2 weeks longer than the current design 

 Within-CU change over 6 months and one year 

 Analogous to Q1, Q3 and Q5 of current design, but current design does not release Q1

6 
Precision levels 

 We estimate a SRS sample size of at least 41,100 to achieve 

the desired precision level specified by the CPI. 

 This assumes no design effects, which would increase the required 

sample size 

 Current design achieves an estimated CV of 1.1% for mean 

total expenditures, again assuming an SRS 

 As outside researchers, we have insufficient information on 

overall design effects, within-stratum standard deviations, or 

costs per stratum, cluster or interview to make reliable 

recommendations on stratification and allocation, or PSU 

subsampling rates 

7 
Weighting Protocol 

 General approach remain unchanged 

 Final Weight = Base Weight x Weighting Control Factor x 

Nonresponse Adjustment Factor x Calibration Adjustment 

Factor 

 We recommend evaluating inputs into the nonresponse 

adjustment factor 

 We will discuss this in more detail later 

8 
Survey Design: Overview 

 An initial face to face interview 

 CU demographic characteristics (including income) 

 Technology ownership and use 

 Global questions for past year expenditures 

 Questions on expenditure monitoring by the CU 

 Retrospective questions on past year purchase of low frequency, high cost 

items (e.g., automobiles) 

 Training as to what and how to record information 

 An electronic diary recording device (e.g. tablet computer) with a 

web-based & computer-assisted diary 

 Separate diaries for each member of the CU ages 16 and older 

 30 day diary collection period 

 Additional hardware to scan barcodes and capture receipts, bills, and 

other documents electronically 

9 
Survey Design: Overview (2) 

 Memory ‘triggers’ 

 Paper portable diaries 

 Training to use CU-owned electronic devices as portable diaries 

 Placement of paper mini-diaries for children ages 7 to 15 

 Electronic file cabinets for CU members to upload electronic receipts 

 Ongoing monitoring of compliance throughout the one-month 

diary period 

 Wrap up interview 

 Scan receipts as needed 

 Review expenditures to collect payments that may not have been captured 

in the diary (e.g., automatic deductions) 

 Adjudicate reimbursements (e.g. medical expenses) 

 Retrospective questions as needed to establish as complete a record as 

possible for the CU 

10
Field Protocol 

11

Interviewers 

contact CU and 

establish eligibility 

Initial interview: 

CU-level 

characteristics + 

training 

Diary placement 

and initial 

completion: Week 

1 

Week 2: Diary 

completion; 

Follow-up calls 

Week 3: Diary 

completion; 

Follow-up calls 

Week 4: Diary 

completion; 

Follow-up calls 

Day 30: I'ers pick 

up equipment, 

review receipts, 

final questionnaire 
Face to Face interview 

 In person recruitment and initial interview 

 Identify CU membership 

 Collect demographic and socioeconomic information, including 

income 

 Past month & past year 

 Retrospective questions focusing on major purchases 

 During the past 12 months, have you or anyone in your family purchased a 

car, sport utility vehicle, minivan, or truck? 

 Global questions 

 How much do you spend on food in an average week? 

 How much are your monthly mortgage payments? 

 How much is your total yearly homeowner’s insurance premium? 

 In the last month, how much did you and your family living there pay for 

each of these transportation related expenses....Gasoline? Repairs and 

maintenance? Parking and carpool? Bus fares and train fares? Taxicabs? 

Other transportation? 

 Expenditure monitoring behavior 

12
Computer-assisted diary 

 Completed by all members of the CU 

 Tablet computer for all consumer units 

 Eliminates potential mode effects for those with and without internet access 

 Permits individual confidential IDs for each CU member to log in 

 Web-based instrument 

 Online web questionnaire for persons with broadband internet access at 

home 

 Information automatically reported to data collector 

 Compliance can be monitored 

 Provide wireless data plan access for persons without broadband internet 

access (about 34% in 2010) 

 Computer-assisted instrument 

 Identical questionnaire to web instrument, but data stored on tablet 

 Provides same mode for those without broadband internet access at home 

or for whom wireless data plans not possible 

13
Computer-assisted diary (2) 

 Four week reporting period 

 Balance between costs of recruiting and training on equipment and 

respondent burden 

 Empirical literature is many decades old; does not reflect use of 

technology 

 CUs report something every day, even if it’s simply that they made no 

purchases 

 Expands within-CU analytic ability across an entire month 

 Use of ‘pick lists’ for previously purchased items 

 Source and type of expenditure cues 

14
Barcode and Receipt Scanning 

 Goal: Simplify the task of data entry into the diary for the CU 

as much as possible 

 Hypothesis: If CU data entry is eased by record keeping, then they 

will be more likely to keep records 

 Goal: Provide electronic access to receipts and records in a 

confidential, secure manner directly linked to a diary entry 

 Hypothesis: Directly linking record keeping to the survey task will 

improve reporting 

15
Barcode and Receipt Scanning (2) 

 Barcode readers 

 Advantage: Detailed information about each item with a barcode 

 Disadvantage: No price information; not everything has a barcode 

 Stand-alone vs. apps 

 Stand-alone: Ease of use; storage capacity; example: Scanfob 2002 

 Apps: potentially familiar; additional portable diary device; Example: 

Barcode Scanner; RedLaser; ShopSavvy

 Receipt scanners 

 Advantage: Capture details about item, cost, details on discounts and 

coupons 

 Disadvantage: May be clunky; not all transactions yield receipts 

 Stand-alone vs. apps 

 Stand-alone: Interface with device; designed for expense reports, not 

itemized costs; example: NeatReceipts 

 Apps: Use camera; may not be easy to capture all details on long receipts; 

Example: ProOnGo 

16
Memory Triggers 

 Small “Portable” diary 

 Cell phones, smart phones, PDAs for “real time” capture of 

pictures or voice diaries 

 Paper portable diaries for those who prefer paper 

 7 to 15 year olds: paper? Electronic? 

 IVR “drop boxes” 

 Electronic receipts to personalized “file cabinet” 

 Interface with existing financial software, e.g., Point of 

Purchase information from mint.com 

17
Feasibility Study 

 Conducted by Mathiowetz and graduate students 

 Use of iPad2, iPod Touch, Short Questionnaire developed in 

Qualtrics, several different free or low cost apps 

 Maintained “diary” for two weeks 

 Questions of Interest 

 Is this possible? 

 How burdensome? 

 How costly is the development? 

 How difficult to train user? 

 Results 

 Possible to develop with little money and time using currently available 

applications, hardware, and software 

 Possible to train those of us who are technologically challenged 

 Of course, not recommending this approach—but 

demonstrates that the recommendation is not “pie in the sky” 

18
Example Diary: Requires 

data entry every day 

concerning purchases, 

bills, and services. 

Feasibility Study Options for Data Entry: 

1. Scan receipts and create individual items from 

receipt

2. Barcode items 

3. Keying the information 
Example: Prizmo is a 

multi-purpose 

document and image 

scanner with built-in 

Optical Character 

Recognition (OCR) 

made by Creaceed 

SPRL 

Image obtained from: http://www.creaceed.com/prizmo/iphone/
Importing Receipts 

Receipts are imported into the 

application either through 

stored photos on the 

device, or by taking a image 

of a receipt in the 

application itself. 
 After importing, images may 

be altered to improve the 

accuracy of the optical 

character recognition. 

 This includes: Crop, 

perspective, white balance, 

and image rotation. 

 The user is also asked to 

select the region in which 

prices and labels are 

displayed on the receipt 

itself. 
Optical Character Recognition of Receipts 

After the user has 

selected 

preferences for 

the imported 

image, the 

application 

performs an 

automatic scan to 

detect labels and 

prices for 

individual items. 
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The output shows the user the 

individual items from the receipt. 

The user is free to edit the 

details of items or delete 

information that is not needed. 
Storage and Exporting of Receipts 

Receipts are stored 

locally on the device 

itself, but may be 

exported through email 

or various cloud 

services. 

Images may be exported 

as the original receipt 

or as a .csv file that is 

already broken up in to 

a grid format 

separating individual 

items and prices. 
Example of a handheld scanner. 

http://www.serialio.com/
The participants can scan the barcode information right 

into a text field provided as part of the diary. 

http://www.serialio.com/
Other information about the products can be keyed directly 

with the onscreen keyboard 

http://www.serialio.com/
ProOnGo Example: You can use pictures of receipts to capture the 

expense 
This is an example of a receipt being used to capture this purchase 

from the bookstore 
From the receipts the app extracts the main information such 

as where the expense is from, the total, and the date 
As you can see this application automatically retrieved the proper 

information from this receipt. 
The iPod touch can be used to capture 

expenses that don't usually offer receipts 

http://blog.travelpod.com/travel-photo/emmaroach/1/1270093417/parking-meter.jpg/tpod.html
To remind oneself of the expenses throughout the day one 

could record notes using the voice memos aspect of the iPod 

touch. 

http://movies.apple.come/fr/ipodtouch/features/voice-memos.html
The notes application on 

the iPod touch would allow 

participants to write 

reminders of their 

purchases on the go. 
Information from Notes 

can be referenced by the 

respondent or can be 

“bumped” from the iPod 

Touch (or similar device) 

to the tablet used for diary 

data collection 
Another example of how one can use the iPod 

touch to capture expenses. 
Expenses without receipt can be manually entered into this 

application and then linked to the survey fields. 
The results could be a daily report of the barcodes of all the 

products purchased, along with reference receipt and bill 

statement information 
Create 

dynamic pick 

lists for future 

purchases of 

the same item. 

Disclaimer 

 Not advocating a particular product 

 Our only goal was to address whether in 2011 what we are 

recommending is possible 

 No budget 

 No design team 

 No means by which to modify existing product 

 Many of the products and apps are modifiable 

 Used by low tech and high tech individuals 

44
Engaging the Respondent 

 Monetary incentives 

 Methodological experiment recommended for identifying prepaid 

vs. promised; CU-level vs. person level 

 “Information Exchange” 

 What would be beneficial and of interest to CU members? 

 Summary of expenditures 

 Comparison to other CUs of comparable size, region and 

household composition 

45
Alternative Data Sources 

 Use as benchmarks or for insights into survey errors 

 Current research indicates significant issues in linkage, 

inaccuracies in records, consent for linkage (where necessary), 

missing data in records 

 Federal data sources as benchmarks 

 MEPS

 FoodAPS 

 RECS 

 Non-federal data sources as insights into survey errors 

 Location, type and quantities better reported than prices 

 Add to sample file for monitoring of nonresponse errors 

46
Risks 

 Extension of diary period 

 Technology 

 Data user needs 

47
Methodological Experiments 

 Recommended Methodology Experiments 

 Length of Diary and Effect of Technology Experiments 

 Technology Training 

 Monetary Incentives 

 Design Features Requiring Further Development 

 The use of multiple formats of memory trigger diaries and receipts 

 The level and frequency of interviewer-respondent interaction over the 

diary month. 

 The incorporation of respondents’ financial management and tracking 

systems. 

 The incorporation of feedback mechanisms for responding consumer 

units. 

48
Experiment #1: 

Length of Diary and Effect of Technology Experiments 

 Factor A: Length of the diary field period 

 One week vs. Two weeks vs. Four weeks vs. Six weeks 

 Factor B: Mode of diary 

 Tablet diary: Respondents are given the tablet diary with the webbased questionnaire, scanner and bar code reader described above. 

 Paper diary: Respondents are given the current paper diary. 

 The Comparison: Interviewers conduct the initial interview as outlined in 

Section III above. The tablet with the web diary or the current paper diary 

is placed in the CU. The CU is instructed to record all expenditures for a 

total of <1/2/4/6> weeks. Interviewers make follow-up calls as appropriate 

to encourage participation. The interviewer returns on day <7/14/28/42> to 

collect the equipment/diaries and conduct the final interview 

49
Experiment #1: Sample Size and Power 

1 week 2 weeks 4 weeks 6 weeks Total

Electronic 787 cases; 

630 initial Rs 

787 cases; 

591 initial Rs

788 cases; 

552 initial Rs

788 cases; 

551 initial Rs

3150 cases; 

2324 initial Rs

Paper 788 cases; 

630 initial Rs

788 cases; 

591 initial Rs

787 cases; 

552 initial Rs

787 cases; 

551 initial Rs

3150 cases; 

2324 initial Rs

Total 1585 cases; 

1260 initial Rs

1585 cases; 

1182 initial Rs 

1585 cases; 

1104 initial Rs

1585 cases; 

1102 initial Rs

6300 cases; 

4648 initial Rs

50

 0.80 power to detect a 5 percentage point difference in response rates between any 

two main effect groups 

 0.81 power to detect an interaction effect of 4 reported expenditure items 
Experiment #1: Practical insights 

 New design changes both technology and diary recording 

period 

 This experiment experimentally evaluates each with a full factorial 

design

 Evaluate effects on participation and data quality 

 Diary cooperation rates per week, item missing rates, number of goods 

reported, number of receipts scanned; number of items with bar code 

readers used; number of e-receipts sent to email; number of individual 

diaries used; and total dollar amount reported in each expenditure 

category (e.g., Gonzalez, et al. 2009)

 Serves as a Feasibility Study: Other Benefits and Information 

 Durability of the equipment, rate of failure of the devices during the diary 

period and whether the failure rate changes as the diary reporting 

period increases, and safety/security of leaving equipment of this value 

in CU members’ homes 

51
Experiment #1: 

Financial and Time Requirements 

 Assume cost of equipment is between $900 and $1500 for all 

pieces 

 Equipment cost 

 If all sample released simultaneously = $4 million to $7 million 

 If sample released in four random replicates = $1 million to $1.7 million 

 Assuming today’s costs for tablets; technology costs trend downward over 

time 

 Field cost = $1.5 million 

 Assuming $325 per completed interview; may be lower if effort exerted 

is less 

52
Experiment #2: Technology Training 

 Each consumer unit will be instructed on the basics of 

 keeping records, 

 scanning receipts, 

 reading bar codes, 

 emailing e-receipts, 

 calling the in-bound IVR line, and 

 entering information into the diary in all methods. 

 Consumer units will be given a text document containing the 

basic instructions in all methods. 

53
Experiment #2: Technology Training 

 Group 1: Video 

 Brief (15 minute) video training session preloaded on the tablet 

 Video will demonstrate how to enter a “market basket” of goods, service bills, and 

receipts using the tablet computer and equipment. 

 Interviewers will be present while the video is playing, but will not provide instructions. 

 Group 2: In person, basic 

 Interviewers will briefly (15 minute) instruct CUs 

 Interviewer will demonstrate how to enter a “market basket” of goods, service bills, and 

receipts using the tablet computer and equipment. 

 Interviewer will not engage in extensive one-on-one time with the CU using the tablet. 

 Group 3: In person, extended 

 Interviewers will run an extended (30-45 minute) training session on how to use the 

tablet computer and other survey tasks 

 Interviewer will demonstrate how to enter a “market basket” of goods, service bills, and 

receipts using the tablet computer and equipment. 

 Interviewer will engage in practice sessions with the respondent, showing them how to 

scan a practice receipt, asking them to call in to the inbound IVR line to practice memory 

cues, and walking through entering information in a practice diary from three receipts 

from different locations. 

54
Experiment #2: Laboratory Evaluation 

 Administer the first questionnaire for the field data collection 

 Administer the assigned training method 

 Provide respondents with a set of items, records and receipts to enter 

into the diary, reflecting approximately the number of items and types 

of items purchased during a normal week of diary keeping 

 Example: Sacks of groceries, bags from a warehouse or multi-category 

retail ‘big box’ store including purchases that fall into a variety of 

categories (e.g., Costco, Walmart, Sam’s Club and/or Target), a receipt 

for a haircut, utility bills, mortgage or rent bills, gasoline receipts, 

paychecks, and bank statements that reflect automatic transfer 

payments. 

 R will scan items using the barcode scanner, scan receipts, and 

complete the appropriate sections of the diary. 

 Provides a direct measure of accuracy of entering information across 

the three training groups 

55
Experiment #2: Field Evaluation 

 Obtain home address from each lab respondent 

 Interviewer delivers equipment to lab respondent’s house 

 Interviewer will identify whether or not the respondent has a 

high-speed internet connection 

 If not, household will be given a tablet permitting wireless internet 

connection. 

 Expenditure diary will be kept for two weeks. 

 Interviewer will make follow-up calls and visits, as needed. 

 At the end of the two weeks, the interviewers will return to the 

lab respondent’s house to pick up the equipment 

56
Experiment #2: Sample Sizes 

Week Month 1 Month 2 Month 3

1 Recruit n=50 lab 

participants

Group 1: 16

Group 2: 17

Group 3: 17

Start Lab + Diary 

Recruit n=50 lab 

participants

Group 1: 17

Group 2: 17

Group 3: 16

Start Lab + Diary 

Recruit n=50 lab 

participants

Group 1: 17

Group 2: 16

Group 3: 17

Start Lab + Diary 

2 Lab + Diary Lab + Diary Lab + Diary

3 Complete Diary; pick 

up equipment

Complete Diary; pick 

up equipment

Complete Diary; pick 

up equipment

4 Ready equipment for 

next group

Ready equipment for 

next group

End of study

57

0.80 power to detect a difference in 10 items between any two groups 
Experiment #2: Practical Insights 

 Feasibility study 

 Risk of placing equipment in respondent’s homes 

 Durability of equipment 

 Logistics of setup of equipment 

 Measure of accuracy in lab component 

 ‘Real’ field outcomes, as in Experiment #1 

58
Experiment #2: Financial and Time Requirements 

 Total costs for small sample (n=150 total) estimated to be up to 

$75,000 

 Excludes instrument development or programming or development of 

training materials

 Very small samples over three months 

 More power can be obtained with larger samples, but this obviously is 

more costly 

 Small scale seems reasonable for this experiment, given that it 

is best served in a laboratory 

59
Experiment #3: Monetary Incentives 

 Group 1: No incentive 

 Group 2: $10 per consumer unit adult per week promised & $5 

per consumer unit child per week promised 

 Group 3: $10 per week per consumer unit promised 

 Group 4: $10 per week per consumer unit prepaid 

 Dollar amounts adapted from UK’s Food and Living Expenses 

Study 

60
Experiment #3: Practical Insights 

 Group 2 vs. Group 3 

 Evaluate promised CU-level incentives compared to promised 

person-level incentive 

 Group 3 vs. Group 4 

 Evaluate prepaid vs. promised CU-level incentives 

 Group 1 vs. Groups 2, 3, 4 

 No incentive vs. any incentive 

61
Considerations concerning nonresponse 

 Responsive Design 

 Modify data collection efforts given field progress 

 Pre-identify changes to protocol 

 Pre-identify triggers for implementing new protocol components

 Field Effort 

 Phase capacity 

 Calls vs. days

 Key Estimates 

 Field Effort Indicators 

 Response rates, ineligible rates, contact rates, cooperation rates 

 % of CUs visited at least once, during peak times, HPI 

 % of CUs submit data; successfully complete full week; # items reported; 

change in # items reported 

 Key estimates vs. global questions 

62
Considerations concerning nonresponse 

 Monitoring 

 Subgroups 

 Urbanicity, type of PSU, housing tenure (own/rent), housing value, number 

of rooms in the dwelling unit, region, sex, race, educational attainment, CU 

size, and CU income 

 Observations of presence of children; interviewer observations of HU value; 

Merged administrative data 

 Variation in response rates; R-indicators 

 Interviewers 

 Variation in response rates; subgroup response rate variation over 

interviewers 

 New Protocol Components 

 Shorter Diary Period 

 Global Questions Only 

 Increased Incentives 

 Triggers for New Protocol Components 

 Prespecified # of days vs. monitoring for ‘phase capacity’ 

 Monitoring System Requirements 

63
Costs 

 Field Costs 

 Assume $325/successful interview 

 Assume at least 2 field interviews (beginning and end of diary period) 

 Costs = $22.6 million to $32.4 million 

 Technology Costs 

 Assume total 2011 costs of $900 to $1500 

 Costs = $6 million to $12 million 

 Incentive Costs 

 Assume promised $10 / week / CU 

 Costs = $1.33 million 

 Post-Survey Processing Costs 

 Unknown 

 Development Costs 

 Unknown; likely $10-$20 million over three years 

64
Conclusions 

 Radical departure from current CE Design 

 Reduce reliance on retrospective recall 

 Reduce reliance on proxy reports 

 Attempt to minimize burden by harnessing technology 

 Scanners, barcode readers 

 Saving receipts 

 Utilize portable diaries 

 Form of the diary to match the technology of the CU 

 Include CU members as young as 7 

 Integration of all expenditure data for a sampled CU 

 Moves away from two sources of data for various expenditures 

 Preservation of longitudinal features 

 Year to year comparison for CU for a given month 

 Synthetic estimation for quarterly, annual data 

 

65