BLS WORKING PAPERS 

 

U.S. Department of Labor 

U.S. Bureau of Labor Statistics 

Office of Employment and Unemployment Statistics 

The Timing of Maternal Work and Time with Children 

Jay Stewart, U.S. Bureau of Labor Statistics 

Working Paper 425

June 2009

All views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the 

U.S. Bureau of Labor Statistics. 
The Timing of Maternal Work and Time with Children 

 March 2009 

Jay Stewart 

U.S. Bureau of Labor Statistics 

2 Massachusetts Ave., NE 

Washington, DC 20212 

USA 

Stewart.Jay@bls.gov

(202) 691-7376 

Any views expressed are mine and do not necessarily reflect those of the Bureau of Labor 

Statistics. I thank Dori Allard, Bob Drago, Harley Frazis, Irina Paley, participants in the 

IZA Topic Week on Nonmarket Time in Economics, and two anonymous referees for 

their helpful comments and suggestions. 
Abstract 

I use data from the American Time Use Survey to examine how maternal employment 

affects when during the day that mothers of pre-school-age children spend doing enriching 

childcare and whether they adjust their schedules to spend time with their children at moredesirable times of day. I find that employed mothers shift enriching childcare time from 

workdays to nonwork days. On workdays, full-time employed parents shift enriching childcare 

time toward evenings, but there is little shifting among part-time employed mothers. I find no 

evidence that full-time employed mothers adjust their schedules to spent time with their children 

at more-preferred times of day, whereas part-time employed mothers shift employment to later in 

the day. 
Introduction 

The effect of maternal employment on child development is a hotly-debated topic. 

Maternal employment can enhance child development if it results in additional resources being 

available for enriching types of activities, such as reading to and playing with children. But it 

can be detrimental if working crowds out childcare time. Sociological studies have shown that 

maternal employment results in mothers spending less time with their children, but that mothers 

go to great lengths to reduce the impact on childcare time by cutting back on other activities such 

as sleep and household work. 

Another avenue by which maternal employment might negatively affect child outcomes 

is through the timing of childcare activities. Psychological research on circadian rhythms 

suggests that some times of day are likely to better than others for parent-child interactions. 

Employment may result in parents spending time with their children when that time is less 

valuable. If this is the case, then we would expect mothers to adjust their schedules so they can 

spend time with their children at times of day when the benefits from these activities are greater. 

In this study, I examine how employment affects the when during the day that mothers 

spend time with their children in enriching childcare activities. I then look for evidence that 

mothers adjust their schedules to reduce the impact of employment on the timing of childcare 

activities. The main focus of this study is on the mothers of pre-school-age children (ages 0-4), 

because they have more flexibility with respect to the timing of childcare activities than do the 

mothers of school-age children. 

Background 

Several recent studies (Baum 2003, Ruhm 2004, James-Burdumy 2005) have examined 

the effect of maternal employment on children’s cognitive development. The results are 
- 2 -

somewhat mixed, but they generally show that maternal employment has a detrimental effect on 

child development as measured by scores on standardized tests.1 These authors have very little 

to say about the mechanisms by which this occurs although Rhum (2004) and James-Burdumy 

(2005) suggest that research on these mechanisms would be useful, with James-Burdumy 

specifically mentioning time-diary data. The most obvious mechanism is through the amount of 

time spent in enriching childcare, such as playing with and reading to children. 

A number of studies have examined the effect of maternal employment on childcare time, 

and has found that employed mothers spend less time with their children than nonemployed 

mothers.2

 And a recent study by Cawley and Liu (2007) focused on the effect of maternal 

employment on time spent in education-related activities and found that employed mothers spend 

less time reading to their children and helping them with their homework, as well as less time 

playing with children. But there has been almost no research on when this care is provided.3

 

The timing of childcare matters because not all time is equally valuable. Time spent in 

enriching childcare activities is likely to be more beneficial for the children and more enjoyable 

for their mothers at times when the children are more receptive to learning and their mothers are 

not tired. If it is the amount of quality-adjusted time with children that matters and employment 

causes their mothers to shift enriching childcare to “less-productive” times of day, then looking 

only at the amount of time in enriching childcare understates the full impact of employment on 

maternal time with children. 

 

1

 Baum (2003) and Ruhm (2004) find that maternal employment has negative effects on test scores, while JamesBurdumy (2005) finds both negative and positive effects depending on the age of the child when the mother worked. 2

 For example, see Bianchi (2000, 2006) and Bianchi, Robinson, and Milkie (2006). 3

 Craig (2006) presents some evidence that employed mothers are less likely to spend time with their children in the 

morning and the afternoon. 
- 3 -

The large body of research on circadian rhythms examines how biological functions vary 

over the course of the day.4 One facet of this research focuses on individuals’ preferences for 

certain times of day, with individuals being classified as preferring either mornings or evenings. 

These studies are based on the Morningness-Eveningness Questionnaire (MEQ), which is 

designed to assess subjects’ preferences.5

 Most of the research has focused on teenagers and 

adults. Teens and younger adults generally prefer afternoons and evenings, while older adults 

tend to prefer mornings. Other studies have shown that performance on complex tasks is better 

at preferred times of day, whereas performance on routine tasks is invariant to the time of day. 

There is less research available on the time-of-day preferences of young children. Two 

studies have examined the morningness/eveningness of 8-16 year olds (Kim, et al 2002) and 2-6 

year olds (Wickersham 2006).6

 The Kim, et al study found that younger children prefer the 

mornings, while older children prefer afternoons and evenings. The crossover point for this 

change is at about age 13. The Wickersham study found that pre-school-age children prefer 

mornings, and that the preference is quite strong in two- and three-year-olds. If young children 

also perform better on complex tasks at their preferred time of day then we might expect 

enriching care to be more valuable, and thus more “productive,” in the morning than in the 

evening, with the afternoon falling somewhere between the two. 

The key points to take away from this research are that it matters when during the day 

that parents spend time with their children and that children generally prefer times of day that 

coincide with normal work hours. The times of day that parents actually choose to spend time 

 

4

 This discussion is based on Hasher, Goldstein, and May (2005), which contains a nice summary of the relevant 

research on this topic. 

5

 The MEQ asks respondents about preferred times for doing certain types of activities, as well as preferred times for 

waking up and going to sleep. 

6

 In the Wickersham study, the MEQ was adapted so that parents could answer for their children. 
- 4 -

with their children will depend on their own time-of-day preferences, their children’s 

preferences, and the productivity of time spent in other activities at different times of day. 

A Simple Model of Timing 

 To see how differences in the productivity of time spent in childcare and other activities 

over the course of the day affect the timing of those activities, consider a simple two-stage model 

of timing.7

 In the first stage, mothers maximize utility and determine the optimal amount of time 

to spend in each activity during a given period of time, such as a day.8

 In the second stage, they 

determine how that time is distributed over the sub-periods within the day.9

 For simplicity, I 

assume that there are two sub-periods and two activities. 

In the first stage, mothers receive utility from time spent in enriching childcare, A, and all 

other activities, X, which include leisure, household work, and working for pay.10 The 

productivity of time spent in each of these activities is given by the functions Γ(γ) for activity A

and Θ(θ) for X, where the arguments γ and θ are vectors of productivities for the sub-periods and 

Γi, Θi >0 for i = 1,2. Each mother solves the following first-stage optimization program: 

Max A,X U( ) Γ() () γ A,Θ θ X s.t. A+ X = 2T , 

 

7

 There is relatively little research on the timing of activities. An early paper by Winston (1982) presents a 

theoretical model of timing. Two other studies examine the timing of work activities (Hamermesh, Knowles, and 

Pocock 2006) and the coordination of husbands’ and wives’ time with children (Paley 2006). Hamermesh (2005) 

and Hamermesh and Donald (2007) examine the effect of employment on the timing of other activities. Hamermesh 

(2002) and van Klaveren and van den Brink (2007) examine the synchronization of husbands’ and wives’ work 

schedules. My theoretical model is most similar to the one in Conolly (2008), who examines the effect of weather 

on the timing of work and leisure activities. 

8

 I do not model the joint decision-making of mothers and fathers. The model is intended mainly to show how timeof-day preferences affect the timing of work and enriching childcare and to help guide the empirical work. 9

 Technically, it would be more realistic to solve the utility maximization problem in one stage with the time spent in 

each activity at each time as an argument in the utility function. But it is easier to see the intuition in the two-stage 

model. 

10 The utility from X therefore includes utility derived from goods purchased from labor market earnings as well as 

the utility of leisure and the utility derived from household production. A more traditional model that includes 

market work and leisure as separate activities, includes consumption of market goods, and explicitly models 

household production would be more complicated but the important results would not change. 
- 5 -

where T is the total amount of time in each sub-period. The solution to this program is 

straightforward and the optimal values of A and X will be denoted as A* and X*. 

 The second stage maximization program can be written as: 

( ) ( ) ( ) ( ) Max 1 1 2 2 1 1 2 2 u = γ f a + γ f a +θ g x +θ g x

a x T

a x T

x x X

a a A

+ =

+ =

+ =

+ =

2 2

1 1

1 2

1 2

*

s.t. *

where ai and xi denote the time spent in childcare and in other activities in sub-period i, f′,g′ > 0, 

and f′′,g′′ < 0. The equilibrium condition for this program is: 

 (1) () ( ) ( ) ( ) 1 1 1 1 2 2 2 2 γ f ′ a −θ g′ T − a = γ f ′ a −θ g′ T − a . 

Thus parents equate the difference between the marginal utilities of the two activities across the 

two sub-periods, where the difference is equal to the difference between the lagrangian 

multipliers on the two constraints.11 This condition along with the assumptions regarding the 

functional forms of f(·) and g(·) guarantee that, all else equal, parents will spend more time with 

their children when that time is more productive. More generally, an increase in the productivity 

of A in sub-period 1, γ1, affects a1, and hence a2, directly though changes in the relative 

productivities of A and X in sub-periods 1 and 2, and indirectly through changes in A* and X*. 

The former effect is akin to a substitution effect, while the latter is akin to a scale effect. 

The substitution effect can be seen by holding A* (and X*) constant and totally 

differentiating the second-stage equilibrium condition in equation (1) with respect to γ1 using the 

implicit function rule, yielding the following: 

 

11 The inequality of the marginal products is an artifact of the two-stage optimization program and the adding-up 

constraint in the second stage. 
- 6 -

(2) ( ) () () () () 0 *

2 2

*

2 2

*

1 1

*

1 1

*

1

1 0

*

1

*

> ′′ + ′′ + ′′ + ′′

− ′ =

= f a g x f a g x

f a

d

da

dA γ γ θ γ θ . 

Similarly, 

(3) ( ) () () () () 0 *

2 2

*

2 2

*

1 1

*

1 1

*

1

1 0

*

1

*

< ′′ + ′′ + ′′ + ′′

− ′ =

= f a g x f a g x

g x

d

da

dA θ γ θ γ θ . 

Thus an increase in the productivity of activity A in sub-period 1 causes parents to shift time in 

activity A from sub-period 2 to sub-period 1, while an increase in the productivity of activity X in 

sub-period 1 results in a shift in the opposite direction (holding A* and X* constant).12 The 

adding-up constraint implies that: 

(4) 0

1 0

*

1

*

>

dX = d

dx

θ

 and 0

1 0

*

1

*

<

dX = d

dx

γ

 The sign of the scale effect is ambiguous. Differentiating the first-stage equilibrium 

condition and arranging terms yields: 

( )

( ) ⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛ Γ ⋅ −

⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛ − Γ ⋅ − +

=

Γ Θ

Γ Θ

U A U X

U A U X

X

A

X

A A

d

dA

* ,

*

,

* ,

*

,

*

1

1

*

1 1

1 1 1

δ δ

δ δ

γ γ

γ

<

=

> 0, 

where , 0 1 δ U ΓA < is the own elasticity of marginal utility with respect to quality-adjusted time in 

A (which equals Γ·A) and δ U1 ,ΘX is the elasticity with respect to quality-adjusted time in X

 

12 If the daily production function is specified as ( ) 1a1 f γ instead of ( ) 1 a1 γ f , then 1

*

1 da dγ is positive as long as the 

elasticity of marginal product with respect to quality-adjusted time is greater than −1. If the marginal product 

function is elastic, then the amount of quality-adjusted time increases, but actual time decreases. The result in 

equation (2) also depends on the assumption that utility in the second stage is additively separable across activities 

and time periods. However, this assumption seems reasonable over short period of time such as a day or so. 
- 7 -

(which equals Θ·X). If 1 , 0 *

*

, 1 1 <⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛ − < U ΓA − U ΘX X

A δ δ then 0

1

*

>

dγ

dA . If A* is small relative to X*, 

as would be the case for enriching childcare activities, then 0

1

*

>

dγ

dA if 1 , 0 1 − < δ U ΓA < . 

Implications 

Although I did not explicitly model multiple days above, I can still shed light on 

workday-nonwork-day comparisons. Suppose that the productivity of enriching childcare is 

higher in sub-period 1 (daytime) than in sub-period 2 (evening) and that productivity does not 

depend on whether the day is a workday— N W N W

1 1 2 2 γ = γ > γ = γ , where the W and N superscripts 

denote workdays and nonwork days. Now suppose that other activities are assumed to have 

either: (1) the same productivity in both sub-periods on nonwork days and higher productivity in 

sub-period 1 ) ( 1 1 2 2

W N N W θ >θ =θ = θ on workdays, or (2) higher productivity in both sub-periods 

( ) 1 2 1 2

W W N N θ = θ > θ = θ on workdays.13 Higher productivity of other activities in sub-period 1 

could reflect the higher productivity of work during normal work hours due to the coordination 

of work activities (see Hamermesh, Knowles, and Pocock 2006). Equal productivities in both 

periods could reflect employers’ coverage requirements, which might be the case for nurses or 

retail workers. 

In both cases, we would expect to see parents shifting enriching childcare time from 

workdays to nonwork days. On nonwork days, we would expect them to spend time with their 

children mostly in sub-period 1 and shift other activities to sub-period 2. The timing of work and 

childcare on workdays depends on when work time is more productive. We would expect to see 

parents spend relatively more time working (and less time doing enriching childcare) in sub-

 

13 I am defining workdays as days in which the relative productivity of work is high enough that the parent chooses 

to work. 
- 8 -

period 1 if the productivity of other (work) activities is higher in sub-period 1 and relatively 

more in sub-period 2 if the productivity of other activities is the same in both periods. 

It is important to note that I have not explicitly modeled the mother’s choice of jobs. 

That choice will depend on their productivity (wage) in different jobs, other sources of income 

(especially spouse’s income), and the strength of preferences for spending time with children 

during the day. Regarding the latter, we might expect mothers who have a preference for 

spending time with their children during the evening to work at jobs where sub-period-1 

productivity is higher, while mothers who prefer to spend time with their children during the day 

might be more likely to work at jobs where productivity is independent of time of day. 

Data 

 I use pooled 2003-2007 data from the American Time Use Survey (ATUS). The ATUS 

is a time-diary survey that asks respondents to sequentially describe their activities, which are 

translated into over 400 detailed activity codes, during a 24-hour period.14 For each episode, the 

ATUS also collects the start and stop times, who else was present, and where the respondent 

was. The ATUS also contains demographic information for all household members and labor 

force information (including labor force status and usual hours worked) for the respondent and 

the respondent’s spouse or unmarried partner.15 

I restricted my sample to married women age 18 and older, and defined four sub-samples: 

mothers of children ages 0-4, mothers of children ages 5-9, mothers of children age 10-17, and 

 

14 If respondents report doing more than one thing at one time (such as cooking while talking to a child), only the 

activity reported as the primary (or “main”) activity is coded. However, traveling--even when done in conjunction 

with another activity, such as feeding a child--is always considered the primary activity. The diary day starts at 4am 

“yesterday” and ends at 4am “today.” 

15 For additional details about the ATUS, please see Hamermesh, Frazis, and Stewart (2005) and Frazis and Stewart 

(2007). 
- 9 -

women who are not parents.16 To facilitate comparisons, I excluded mothers who had children 

in more than one age category. Thus the main differences between three sub-samples of mothers 

are the ages of the children (and the mothers), and I interpret any differences in the timing of 

activities to be due to these age differences.17 

For my analysis I defined three broad categories of childcare—routine care (such as 

feeding or bathing), enriching care (such as reading to or playing with children), and other 

childcare (such as dropping off and picking up children)—using the twenty-six activity codes 

that describe care of household children. For enriching care activities, I only included time when 

a child was present.18 One complication that arises when comparing time spent in enriching 

childcare for children of different ages is that activities that might be classified as childcare when 

a child is young may not be when the child is older. For example, riding bikes with a 3 year-old 

may be coded as childcare (030105), while riding bikes with a 9 year-old may be coded as bike 

riding (130104). Since I compare time spent in enriching childcare for mothers with children of 

different ages, my definition of enriching childcare also includes selected leisure activities that 

were done while a child was present. The main leisure activity that I excluded is television 

watching.19 (See the Appendix for detailed definitions.) 

Table 1 shows the average number of hours per day spent in childcare activities by 

employment status. Comparing the “all days” columns we can see that, except for “other 

childcare,” nonemployed mothers spend the most time in childcare, while full-time employed 

mothers spend the least. Nearly half of childcare done by mothers of 0-4 year-old children is 

 

16 Here, “children” refer to own children (including adopted and step children) who live with their mothers. 17 The differences could also be due to cohort effects. 18 I make this restriction because some activities, such as reviewing homework or preparing for a project, can be 

done when the child is not present. 

19 One leisure activity that is potentially problematic is socializing when other adults are present, because it is 

possible that the children have been “dragged along” and are not part of the activity. I reran the analysis using an 

alternative definition of socializing and excluding it altogether, and the results were nearly identical. 
- 10 -

routine, while routine childcare accounts for less than one-third of childcare done by mothers of 

5-9 year-olds. Mothers of older children (10-17) spend very little time in routine childcare, and 

time spent in enriching childcare is mostly leisure activities done with these children. 

Childcare on Workdays and Nonwork Days 

Table 1 also shows how employed mothers shift childcare from workdays to nonwork 

days. Workdays are days on which the mother spends any time working at a location other than 

her home.20 It is also important to note that, because the ATUS collects data for only one day, I 

do not directly observe the shifting of childcare activities. Instead, I compare employed mothers 

on workdays and nonwork days, noting that whether a mother is observed on any particular day 

is determined randomly through the procedure for assigning respondents to days of the week.21 

Overall, employed mothers of 0-4 year-old children spend about 60 percent more time 

per day doing childcare on nonwork days than they do on workdays, but there are notable 

differences between full- and part-time employed mothers and by type of childcare. Part-time 

employed mothers spend about 35 percent more time in routine childcare on nonwork days than 

on workdays, whereas full-time employed mothers spend 60 percent more. For both full- and 

part-time employed mothers, enriching childcare is shifted from workdays to nonwork days to a 

much greater degree than is routine care. This is as we would expect because many routine 

childcare activities, such as feeding and dressing, must be done every day. Childcare time is 

shifted in the other direction for “other childcare,” which includes transporting children. Fulltime employed mothers spend considerably more time in other childcare activities on workdays 

than on nonwork days, which likely reflects time spent getting children to and from daycare or 

 

20 The small number of days that mothers work exclusively at home are included with nonwork days because 

mothers who work at home have considerable flexibility with regard to when they spend time with their children. 

21 The key thing is that the probability that a given day is selected for an interview is independent of the activities 

that are done on that day. 
- 11 -

preschool. In contrast, part-time employed mothers spend an equal amount of time on work and 

nonwork days. 

Looking at the panels for mothers of older children (5-9 year-olds and 10-17 year-olds) 

we can see that time spent in both routine and enriching childcare decline as the children get 

older, with the decline being much larger for routine care. As with the mothers of pre-school-age 

children, childcare is shifted from workdays to nonwork days. Again, enriching childcare is 

shifted to a much greater degree compared to routine care. 

These findings are consistent with the prediction that parents will shift childcare time 

from workdays to nonwork days. They are also consistent with results in Hamermesh and 

Donald (2007), who find that the fixed costs associated with working affect the timing of nonwork activities, and Stafford and Yeung (2005), who find that children spend more time with 

their parents on weekend days than on weekdays. 

The Timing of Childcare 

 I now turn to the question of when during the day mothers spend time in enriching 

childcare. The research on circadian rhythms suggests that mornings may be the best time (from 

the child’s perspective) for enriching care. However, because it is the mother’s utility that is 

being maximized and productivity depends on both mother’s and children’s time-of-day 

preferences, it is possible that mornings are not the most productive time of day. Although I 

have no direct information on these preferences I can infer when parents prefer to engage in 

enriching childcare by looking at nonemployed mothers and employed mothers on their nonwork 

days, when they are not constrained by work schedules.22 Thus, I will determine whether 

 

22 Comparing nonemployed mothers to employed mothers is potentially problematic because the employment 

decision may be related to unobserved differences in time-of-day preferences. For example, mothers who prefer to 
- 12 -

employment affects the timing of enriching care by comparing workdays to nonwork days of 

employed mothers and to all days of nonemployed mothers. If there is no employment effect on 

timing then, apart from differences in the amount of time spent with children, the distribution of 

time spent in enriching childcare over the course of a day should be the same on both work and 

nonwork days. 

 Figure 1 shows the distribution of enriching childcare time for mothers of 0-4 year-old 

children on workdays and nonwork days by employment status. The height of each bar is the 

fraction of total enriching childcare time that is done during that hour. For example, 22 percent 

of the time that full-time employed mothers spend on enriching childcare on workdays is done 

between 7:00pm and 8:00pm. 

 The graphs for all days of nonemployed mothers and for nonwork days of employed 

mothers are strikingly similar, with the time spent in enriching childcare being distributed fairly 

uniformly throughout the day. About 40-48 percent of enriching childcare is done between 

9:00am and 4:00pm, while 16-20 percent is done between 7:00pm and 10:00pm. The fact that 

enriching childcare is fairly evenly distributed over the day seems to contradict the circadianrhythm research. But, it is important to keep in mind that both the children’s and their mothers’ 

time-of-day preferences come into play here. The distributions of enriching childcare time 

suggest that, in terms of the theoretical model, γ1 and γ2 are not that different from each other. 

This, along with the assumption that f(·) exhibits diminishing marginal productivity, implies that 

the total value of enriching childcare is maximized when mothers spend about the same amount 

of enriching childcare time in each sub-period 

 spend time with their children in the evenings may be more likely to be employed full time. If this is the case, we 

would expect these mothers to concentrate their childcare activities in the evening on their nonwork days as well. 
- 13 -

The distribution of enriching childcare time done on workdays by full-time employed 

mothers is quite different from that on nonwork days, with much of the time on workdays 

concentrated in the evenings. Over 40 percent of enriching childcare is done between 7:00pm 

and 10:00pm, while only 15 percent is done between 9:00am and 4:00pm. The distribution of 

enriching childcare done by part-time employed mothers on workdays lies between these two 

extremes, but looks more like the nonwork day distributions. Forty percent of enriching 

childcare is done between 9:00am and 4:00pm, and 27 percent is done between 7:00pm and 

10:00pm. 

To quantify the differences in the distributions and the amount by which workday 

distributions diverge from nonwork day distributions, I used a dissimilarity index to compare 

average workdays and nonwork days. For each pairwise comparison, the weighted absolutedeviation index, TWAD, is given by: 

( )

( )

( ) ∑ ∑ = ∑ ∑ = = =

⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛ − =⎟

⎟

⎠

⎞

⎜

⎜

⎝

⎛

+

+

×

+

− =

24

1

24

1

24

1

24

1

h 2

h h

h h h h h

h h

h h

h h

WAD

a b

a b

a b

a b

a b

T , 

where ah, bh are the fractions of time spent in enriching childcare in each hour of the day on days 

a and b, and a and b refer to groups defined by their workday and employment status. The index 

ranges in value from 0 to 1, where 0 indicates that the distributions are identical and 1 indicates 

that there are no times of day in common.23 

This index has a natural interpretation. It is equal to the fraction of enriching childcare 

time that one group must reallocate to different times of day in order to make their two 

 

23 The index is designed to measure between-group differences in time spent in all activities (for example, 

measuring how differently men and women use their time). In my analysis, the groups are defined by employment 

status and whether or not the day was a workday (for example, comparing work and nonwork days for full-time 

employed or comparing nonwork days of full-time employed and nonemployed). And the activities are defined by 

time of day, where time spent in enriching childcare at each hour of the day is viewed as a separate activity. See 

Stewart (2006) for more details about the index. 
- 14 -

distributions identical. Thus, the index values for workday-nonwork day comparisons equal the 

fraction of enriching childcare time that mothers shift due to market work. 

The index values for pairwise comparisons of the three nonwork days (full-time 

employed, part-time employed, and nonemployed) are all less than 0.10, which indicates quite a 

bit of similarity (see Table 2). This is strong evidence that employed mothers have the same 

time-of-day preferences for enriching childcare as nonemployed mothers, and that the shifting of 

enriching childcare time from workdays to nonwork days does not affect the timing of these 

activities on nonwork days. As expected, we see large differences when comparing the 

workdays of full-time employed mothers to nonwork days (the index values are in the 0.34-0.40 

range). The index values for comparisons to the workdays of part-time employed mothers 

confirm our earlier observation that the workdays of part-time employed mothers are much 

closer to nonwork days than they are to the workdays of full-time employed mothers. The index 

values for comparisons to nonwork days are in the 0.14-0.18 range. The index of 0.32 for the 

workday-to-workday comparison of full- and part-time employed mothers is about the same 

magnitude as the index value for workday-to-nonwork-day comparison for full-time employed 

mothers. Another way to quantify these differences is to compute the amount of time that would 

have to be rescheduled. Using the average day of a nonemployed mother as a common 

reference, full-time employed mothers would have to reschedule about 16 minutes per workday 

(or about 71 minutes per week) of enriching childcare time compared to 11 minutes per workday 

(30 minutes per week) for part-time employed mothers.24 

To summarize, the results in Table 1 show that full-time employed mothers shift 

enriching childcare time from workdays to nonwork days, while Figure 1 and Table 2 show that 

 

24 Full-time employed mothers of 0-4 year olds work 4.5 days per week on average, while part-time employed 

mothers work 2.8 days per week.) 
- 15 -

they shift enriching childcare time to later times of day on workdays. This shifting reduces the 

value of enriching childcare time not because the productivity parameter (γ) is lower in the 

evening, but because the enriching childcare production function exhibits diminishing marginal 

productivity and the total value of enriching childcare time is maximized when enriching 

childcare time is distributed evenly throughout the day. Part-time employed mothers also shift 

enriching childcare time from workdays to nonwork days, but on workdays there is very little 

shifting to later times of the day. Given mothers’ preferences for spreading enriching childcare 

time evenly throughout the day, it would be reasonable to expect them to adjust their work 

schedules so that they can spend more time with their children at preferred times of day. 

 The Timing of Work 

To examine how time-of-day preferences affect when during the day that mothers of 0-4 

year olds choose to work, I would like to know when these mothers would work if the children 

were not present. Since I cannot make this comparison, I instead compare the employed mothers 

of 0-4 year olds to the employed mothers of 5-9 year olds, 10-17 year olds and employed women 

who are not mothers. 

The most appropriate control group would appear to be the mothers of 5-9 year-old 

children. These mothers spend almost as much time in enriching childcare activities as mothers 

of 0-4 year-old children and are likely to have the same characteristics, except that they are on 

average 5 years older. Perhaps more importantly, the distribution of time spent in enriching 

childcare activities by these mothers on nonwork days is similar to mothers of 0-4 year-olds (see 

Figure 2). Like the mothers of 0-4 year olds, 41-48 percent of these mothers’ enriching childcare 

is done between 9:00am and 4:00pm. The main difference is that mothers of 5-9 year olds do 

less enriching childcare between 9:00am and noon and more between noon and 4:00pm. Thus 
- 16 -

the time-of-day preferences of mothers of 5-9 year olds are fairly similar to those of mothers of 

0-4 year olds. 

The key difference between mothers of 5-9 year-olds and the mothers of 0-4 year olds is 

that the mothers of 5-9 year olds cannot spend time with their children when the children are in 

school. In the context of the theoretical model, this implies that γ1 is close to zero on school days 

and that these mothers will spend very little time in enriching childcare activities at these times 

of day. We can see in Figure 2 that both part-time and full-time employed mothers of 5-9 year 

olds spend very little time in enriching childcare activities on workdays, which are mostly school 

days.25 However, the low productivity of enriching childcare time during school hours also 

implies that employed mothers will shift their work schedule so that they work more in the 

morning and early afternoon. This also implies that comparing the mothers of 0-4 year olds to 

the mothers of 5-9 year olds will overstate the extent to which the former adjust their schedules 

to spend time with their children. For this reason, I also compare the mothers of 0-4 year olds to 

the mothers of 10-17 year olds and to women who are not parents.26 

There is potentially a similar problem with the mothers of 10-17 year-old children. 

Again, the productivity of mothers’ enriching childcare time is close to zero when their children 

are in school, which would lead to mothers shifting work to earlier in the day. On the other 

hand, these older children are more independent and it is less critical that a parent be home when 

these older children come home from school. Moreover, these older children prefer later times 

of day (although they may not want to spend that time with their parents). 

 

25 Ideally, I would also like to distinguish between school and non-school days. But the sample is not large enough 

to do so. In the regression analysis, I control for whether the diary day is a school day. 26 Another factor that facilitates mothers’ labor force participation is the availability of before- and after-school day 

care (also known as extended day) that allow parents to drop children off at school before the school day begins or 

to stay at school after the official school day has ended. In 2007 nearly half of all elementary schools offered these 

programs (Snyder, Dillow, and Hoffman 2008, Table 97). 
- 17 -

My final comparison is to women who are not parents. I believe that these women are 

the most appropriate control group because their time-of-day preferences for work are not 

influenced by school considerations but instead are likely determined by their desire to spend 

time with their husbands. Studies by Hamermesh (2002) and van Klaveren and van den Brink 

(2007) support this supposition. Both studies found that married couples synchronize their work 

schedules so that they can spend more time together, but they synchronize to a lesser extent 

when there are children present. 

For each of these comparisons, I estimated a series of linear probability models. I 

restricted my sample to workdays and estimated a separate linear probability model for each time 

of day between 6:00am and 11:00pm at 5-minute intervals (204 equations total). The dependent 

variable equals one if the parent was working away from home at that moment, and the 

independent variable of interest is a dummy variable that equals one if the women was the 

mother of a 0-4 year old. I controlled for the mother’s age and education; her husband’s 

employment status and education; whether the diary day was in the summer, a school day, or a 

weekend; and the amount of time spent working away from home on the diary day.27 

Figures 3 and 4 graph the coefficients on the dummy variables for the presence of 0-4 

year-old children (and no older children) by time of day. Comparisons to each control group are 

shown in separate panels. I constructed 95-percent confidence intervals using robust standard 

errors clustered by geographic identifiers (not shown), and found that most of the individual 

coefficients are not statistically significant. But the significance of individual coefficients is less 

important than whether the difference is statistically significant for blocks of time. To perform 

 

27 School days are defined as non-holiday weekdays between September 15th and December 15th or between January 

15th and May 15th. A day is considered a school day only if school-age children live in the household. Summer is 

the period from June 1st through August 31st. The school-day variable was not included in the equation comparing 

mothers of 0-4 year olds to non-parents. 
- 18 -

these tests, I ran three regressions for every possible 30-minute block of time between 6:00am 

and 11:00pm. The first block of regressions were run for 6:00am, 6:15am, and 6:30am, the 

second block for 6:05am, 6:20am, and 6:35am, and so on. The three equations for each block 

were estimated jointly to properly account for the cross-equation correlation of residuals and to 

facilitate the hypothesis testing. For each block, I tested whether the sum of the three 

coefficients was significantly greater than or less than zero (depending on time of day) using a 

one-tailed test that accounts for clustering as above.28 Times for which the sum of the three 

coefficients are statistically significant are indicated by the bold portions of the graph. 

Figure 3 shows the coefficients for full-time employed mothers of 0-4 year olds. The 

smallest coefficients are for the comparison to mothers of 5-9 year olds, with the difference 

being larger than 0.05 in absolute value at only a few times during the day. There are larger 

differences in the middle panel’s comparison to mothers of 10-17 year-old children, with the 

differences being largest in the early morning and late afternoon. Even so, the coefficient never 

exceeds 0.1 in absolute value. The largest differences are in the bottom-panel comparison to 

non-parents. Mothers of 0-4 year olds are 5-10 percentage points more likely to work at earlyafternoon times and 5-10 percentage points less likely to work in the early evening. This likely 

reflects these mothers’ desire to be home at dinnertime. Even though the differences are 

statistically significant for several blocks of time in the mornings and evenings, they are small 

given that, between 8:00am and 4:00pm, an average of 73 percent of full-time employed women 

are working at any given time. Thus it is clear is that even though full-time employed mothers 

have the same time-of-day preferences as part-time employed and nonemployed mothers 

regarding when they do enriching childcare, it is too costly for them to make large adjustments to 

their work schedules so that they can spend more time with their children earlier in the day. The 

 

28 The tests were run using STATA’s suest command, which allows for clustering. 
- 19 -

lack of variability of work schedules by presence and age of children among full-time employed 

mothers is consistent with the result in Hamermesh (2005) that the presence of children has no 

effect on “temporal variety”—variability in the timing of activities. 

Figure 4 shows the same comparisons for part-time employed women. Here we see 

much larger differences. The top graph indicates that, compared to the mothers of 5-9 year-old 

children, the mothers of 0-4 year olds are less likely to be working during school hours and more 

likely to be working outside of school hours. This is consistent with the prediction from the 

theoretical model that mothers of school-age children will shift work to times when their children 

are in school. The differences are quite large in the mid-morning, with mothers of 0-4 year olds 

being 10-30 percentage points less likely to be working. They are also about 15 percentage 

points less likely to be working during the early afternoon. These differences are statistically 

significant for about three hours in the mid-morning and just under an hour in the afternoon. 

These mothers are 10-15 percentage points more likely to be working in the early morning and 

15-20 percentage points more likely in the early evening. The morning and evening differences 

are statistically significant for blocks of time that are approximately one and three hours long. 

As noted above, these estimates are likely overestimates of the true effect because of the shifting 

of work to school hours by the mothers of 5-9 year olds. 

The differences are smaller when comparing the mothers of 0-4 year olds to the mothers 

of 10-17 year olds, but they are still large. The differences are in the 10 percentage-point range 

in the morning, the 10-15 percentage-point range in the early afternoon, and the 10 percentagepoint range in the evening, with a smaller fraction of mothers of 0-4 year olds working in the 

morning and afternoon. Given that an average of about 55 percent of part-time employed nonparent women work at any given time between 8:00am and 4:00pm, a 10-15 percentage point 
- 20 -

difference translates to an 18-27 percent difference. The period over which the differences are 

statistically significant cover about two hours in the morning and afternoon and about one hour 

in the evening. 

The bottom panel of Figure 4 shows the comparison to women who are not parents, 

which I have argued is the most appropriate control group. Here the differences are somewhat 

smaller than in the other two panels, falling into the 10 percent range for large portions of the 

day. The differences, though large, are statistically significant only for two blocks of time that 

cover a little over two hours in the evening. In interpreting these results, one must keep in mind 

that the positive difference in the evening necessarily implies a negative difference at other times 

of the day. Thus the lack of statistical significance in the morning and afternoon does not mean 

that there is no effect. Rather, it arises because the effect is spread out over a larger portion of 

the day. 

These results indicate that part-time employed mothers of pre-school-age children adjust 

their work schedule so that they work less during the day and more in the evening. This allows 

them to spend more time with their children throughout the day so that their enriching childcare 

time is not concentrated in the evening. 

My analysis has largely ignored fathers, although the regression equations did include 

controls for the father’s employment status and whether he worked full or part time. Ideally, I 

would like to be able to say something about the interaction of mothers’ and fathers’ work time. 

This type of analysis is impossible, because the ATUS collects data from only one household 

member. However, because the vast majority of these husbands work full time and full-time 
- 21 -

employed men work mostly on weekdays, I can make some inferences about how fathers’ work 

schedules affect when their wives work.29 

Table 3 shows how women’s work time is distributed across weekdays and weekends. 

Full-time employed women do most of their work on weekdays and there is very little variation 

by presence and age of children. About 33 of the 35 hours they work per week are worked on 

weekdays. 

There is more variation among part-time employed women in both the number of hours 

worked per week and in the percent of that time that is worked on weekdays. The mothers of 0-4 

year olds work the fewest hours per week, but work the most hours on weekends. Of the 16.5 

hours that they work per week, 2.4 (14 percent) are worked on weekends. The mothers of 5-9 

year olds work the most hours per week (20.0 hours), but work the fewest hours on weekends 

(1.0 hours or 5 percent of all hours). The mothers of 10-17 year olds fall between, working 

about 7 percent of their hours on weekends. Thus, the mothers of school-age children appear to 

be concentrating their work time on weekdays (school days), whereas the mothers of pre-schoolage children appear to work more on days when their husbands are likely to be available for 

childcare. 

Given that the part-time employed mothers of school-age children work nearly all of their 

hours on weekdays, we might also expect them to shift their work hours to times when their 

children are in school. To examine this, I restricted the sample to days when school is in session 

(Sept. 15th – Dec. 15th and Jan. 15th – May 15th) and calculated the fraction of total hours worked 

during school hours (9am – 3pm on weekdays). As a point of reference, full-time employed 

women (regardless of presence and age of children) and part-time employed non-mothers 

 

29 In 2006, about 88 percent of employed married men worked full time. Full-time employed men worked 5.1 days 

per week on average. Of those, 4.4 days (86 percent of workdays) were weekdays and 0.7 (14 percent) were 

weekend days or holidays. 
- 22 -

worked about 55 percent of their total weekly hours during school hours. Part-time employed 

mothers of school-age children worked most of their total weekly work hours—a little over 60 

percent—during school hours. In contrast, part-time employed mothers of 0-4 year olds 

worked only 43 percent of their total weekly hours during school hours. 

All of these results strongly suggest that one of the reasons that mothers of pre-schoolage children work part time is to have the flexibility to schedule work in order to spend time with 

their children throughout the day. For the mothers of school-age children, part-time employment 

allows them to work when their children are in school. The results also suggest that the greater 

ability to choose when they work is one of the attributes that makes part-time work desirable to 

working mothers. This explanation is consistent with the results of Ichino and Sanz de Galdeano 

(2005), who find that the availability of part-time jobs and flexible employment arrangements is 

a more important determinant of maternal employment rates than the availability of formal 

childcare facilities. Their research suggests that many of these part-time employed mothers 

would choose not to work, rather than work full time, if part-time jobs were not available. 

Summary and Conclusions 

The time that parents spend in enriching childcare activities is an important parental input 

to child development, and some recent studies have found that maternal employment can 

negatively affect child outcomes. An extensive literature has examined the effect of maternal 

employment on childcare time. Most of this literature has focused on the amount of time parents 

spend with their children, but has largely ignored when that time is spent. 

The theoretical model predicts that mothers will want to spend more time in enriching 

childcare activities at times of day when those activities are the most productive. Psychological 

research on circadian rhythms suggests that early in the day is the best time for enriching 
- 23 -

childcare, but the productivity of enriching childcare time also depends on the mother’s time-ofday preferences. 

Focusing on mothers of pre-school-age children (ages 0-4), I found that enriching 

childcare activities are distributed fairly evenly over the day for employed mothers on their 

nonwork days and for non-employed mothers. This implies that the productivity of this time is 

about the same at all times of day and that, because the enriching childcare production function 

exhibits diminishing marginal productivity, the total value of enriching childcare time is 

maximized when that time is evenly distributed throughout the day. 

On workdays, full-time employed mothers of 0-4 year olds shift much of the time spent 

in enriching childcare to the evenings. In contrast, the distribution of enriching childcare time 

for part-time employed mothers on their workdays looks much like the distributions for nonwork 

days. Thus, it appears that, while part-time employment affects the amount of time that mothers 

spend doing enriching childcare, it does not have a large effect on when that care is done. 

I quantified the extent of this shifting of enriching childcare time using a dissimilarity 

index. Full-time employed mothers of pre-school age children would have to reschedule about 

40 percent of enriching childcare time on workdays, compared to only 18 percent for part-time 

employed mothers, to make the workday distribution the same as the distribution for 

nonemployed mothers. This translates to 71 minutes per week for full-time employed mothers, 

compared to 30 minute for part timers. 

Turning to the timing of employment, I found evidence that part-time employed mothers 

adjust their schedule so that they can spend time with their children throughout the day. 

Compared to employed women who are not parents, the preferred control group, the mothers of 

0-4 year-olds are 18 percent (10 percentage points) less likely to be working in the morning and 
- 24 -

early afternoon. In contrast, the difference in timing between full-time employed mother of 0-4 

year-old children and other full-time employed women is small, and there is no evidence that 

full-time employed mothers of 0-4 year olds adjust their schedules to spend more time with their 

children during the day. 

These results suggest that mothers who work part time do so not only to spend more time 

with their children, but also to increase the value of that time. And they imply that looking only 

at the amount of time spent in enriching childcare activities understates the full impact of 

maternal employment on the enriching childcare for full-time employed mothers, but not for part 

timers. 

My findings do not necessarily imply that the children of full-time employed mothers are 

worse off because of this shifting of enriching childcare time. These children presumably are in 

daycare or preschool, where they can participate in enriching activities with their teachers and 

other children throughout the day. As is the case when analyzing the effect of maternal 

employment on the amount of time mothers spend with their children, whether children are 

worse off depends on how substitutable this time is for maternal time. 
- 25 -

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- 26 -

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University Press. 
Workdays 

(away from 

home)

Nonwork 

Days* All Days

Workdays 

(away from 

home)

Nonwork 

Days* All Days

Mothers of 0-4 Year-Old ChildrenChildcare (with child < 5) 2.0 3.5 2.6 2.5 4.1 3.5 

Routine childcare 0.9 1.9 1.3 1.3 1.9 1.7 Enriching childcare 0.7 1.4 1.0 1.0 1.9 1.5 Other childcare 0.4 0.2 0.3 0.3 0.3 0.3 Observations 432 511 943 160 365 525 

Mothers of 5-9 Year-Old ChildrenChildcare (with child 5-9) 1.5 2.4 1.8 1.7 2.7 2.3 

Routine childcare 0.5 0.6 0.5 0.6 0.8 0.7 Enriching childcare 0.7 1.4 0.9 0.7 1.5 1.1 Other childcare 0.4 0.3 0.4 0.4 0.5 0.5 Observations 298 299 597 99 227 326 

Mothers of 10-17 Year-Old ChildrenChildcare (with child 10-17) 0.7 1.2 0.9 1.0 1.5 1.3 

Routine childcare 0.1 0.1 0.1 0.2 0.2 0.2 Enriching childcare 0.4 0.9 0.6 0.5 0.8 0.7 Other childcare 0.2 0.2 0.2 0.3 0.4 0.4 Observations 935 961 1896 262 501 763 

* Includes days on which the respondent worked at home and did not work away from home. Table 1. Hours spent in childcare by mothers on their diary day, 2003-2007 ATUS annual averages

Employed full time Employed part time
Figure 1: Distribution of Time Spent in Enriching Childcare by Mothers of 0-4 Year-Old Children

Full-Time Employed on Workdays

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Full-Time Employed on Nonwork Days

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Part-Time Employed on Workdays

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Part-Time Employed on Nonwork Days

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Non-Employed

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm
Table 2: Dissimilarity Index Comparisons of the Distribution of Enriching Childcare on 

Workdays and Nonwork Days - Mothers of 0-4 Year-Old Children

Workday Nonwork Day Workday Nonwork Day Nonemployed

Full-Time Employed

Workday --- 0.342 0.317 0.387 0.399

Nonwork Day --- --- 0.135 0.059 0.093

Part-Time Employed

Workday --- --- --- 0.142 0.176

Nonwork Day --- --- --- --- 0.077

Full-Time Employed Part-Time Employed
Figure 2: Distribution of Time Spent in Enriching Childcare by Mothers of 5-9 Year-Old Children

Full-Time Employed on Workdays

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Full-Time Employed on Nonwork Days

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Part-Time Employed on Work Days

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Part-Time Employed on Nonwork Days

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm

Non-employed 

0

0.05

0.1

0.15

0.2

0.25

6-7am

8-9am

10-11am

Noon-1pm

2-3pm

4-5pm

6-7pm

8-9pm

10-11pm
Figure 3: Difference in Percent of Full-Time Employed Mothers Working 

by Time of Day (Coefficient on Dummy for Presence of 0-4 Year-Old Children

and 95% Confidence Interval)

Comparison to Mothers of 5-9 Year-Old Children

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

6am7am8am9am

10am11am

Noon

1pm2pm3pm4pm5pm6pm7pm8pm9pm

10pm

11pm

Comparison to Mothers of 10-17 Year Old Children 

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

6am7am8am9am

10am11am

Noon

1pm

2pm

3pm4pm5pm

6pm7pm8pm9pm

10pm

11pm

Comparison to Non-Parents

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

6am7am8am9am

10am

11am

Noon

1pm

2pm

3pm4pm

5pm

6pm7pm8pm9pm

10pm

11pm
Figure: 4 Difference in Percent of Part-Time Employed Mothers Working 

by Time of Day (Coefficient on Dummy for Presence of 0-4 Year-Old Children

and 95% Confidence Interval)

Comparison to Mothers of 5-9 Year-Old Children

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

6am7am8am9am

10am11am

Noon

1pm2pm3pm4pm5pm6pm7pm8pm9pm

10pm

11pm

Comparison to Mothers of 10-17 Year-Old Children

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

6am7am8am9am

10am11am

Noon

1pm2pm3pm4pm

5pm6pm

7pm8pm9pm

10pm

11pm

Comparison to Non-Parents

-0.3

-0.25

-0.2

-0.15

-0.1

-0.05

0

0.05

0.1

0.15

0.2

0.25

0.3

6am7am8am9am

10am11am

Noon

1pm

2pm3pm

4pm5pm6pm

7pm

8pm9pm

10pm11pm
Table 3: Distribution of Work Between Weekdays and Weekends by Age of Children and Full-/Part-Time Status

Weekdays

Weekend 

Days All Days Weekdays

Weekend 

Days All Days Weekday

Full-Time Employed

with 0-4 Year-Old Children 6.5 1.0 5.0 83.6 16.9 64.6 7.8 with 5-9 Year-Old Children 6.7 1.1 5.1 85.3 18.6 66.2 7.8 with 10-17 Year-Old Children 6.6 1.1 5.0 82.5 18.5 64.2 8.0 Non Parents 6.7 1.2 5.1 83.8 18.2 65.0 8.0 

Part-Time Employed 

with 0-4 Year-Old Children 2.8 1.2 2.4 50.2 17.1 40.7 5.6 with 5-9 Year-Old Children 3.8 0.5 2.9 62.0 7.1 46.3 6.2 with 10-17 Year-Old Children 3.4 0.7 2.6 58.6 14.8 46.0 5.8 Non Parents 3.5 0.9 2.8 62.6 17.3 49.7 5.7 

Fraction Working on Diary Day

Average Time Spent Working on 

Diary Day

Average 

Diary Da
Routine childcare

030101 Physical care of household children

030109 Looking after children as a primary activity

030301 Providing medical care to household children

Enriching childcare (children of all ages)

030102 Reading to/with household children

030103 Playing with household children, not sports

030104 Arts and crafts with household children

030105 Playing sports with household children

030106 Talking with/listening to household children

030107 Helping/teaching household children (not related to education)

030201 Homework (household children)

030203 Homeschooling of household children

Enriching childcare (children ages 2+)

1201 Socializing and communitating 

120307 Playing games

120309 Arts and crafts as a hobby

120310 Collecting as a hobby

120311 Hobbies, except arts & crafts and collecting

120401 Attending performances

120402 Atending museums

120403 Attending movies/films

1301 Participating in sports

1302 Attending sporting event

Other childcare

030108 Organization and planning for household children

030110 Attending household children’s events

030111 Waiting for/with household children

030112 Picking up/dropping off household children

030199 Caring for and helping household children, not elsewhere classified

030202 Meetings and school conferences (household children)

030204 Waiting associated with household children’s education

030299 Activities related to household children’s education, not elsewhere classified

030302 Obtaining medical care for household children

030303 Waiting associated with household children’s health

030399 Activities related to household children’s health, not elsewhere classified

170301 Travel related to caring for and helping household children

180301 Travel related to caring for and helping household children

180302 Travel related to household children’s education

180303 Travel related to household children’s health

Appendix. Classification of activities among routine care, quality care, and unclassified care

Note: A child must be present during enriching care activities. For children ages 2+, enriching childcare 

includes leisure activities during which the child was present (see text for further details).