Table 1.

Variable definitions.

Variable	Definition
Dependent variable
Loneliness	The extent to which respondents feel loneliness according to the UCLA methodology. The questions asked to measure respondents’ loneliness were “How often do you feel a lack of companionship,” “How often do you feel left out,” and “How often do you feel isolated from others.” The options to respond to these questions were “Hardly ever or never,” “Some of the time,” and “Often.” Loneliness is a binary variable where 1 indicates having feelings of loneliness some of the time or often, and 0 otherwise. As an alternative, we measured loneliness using the question “How often do you feel lonely” (1 being never and 5 being often or always). This alternative measure of loneliness as a binary variable where 1 indicates feeling loneliness often or always, some of the time, and occasionally, and 0 otherwise.
Explanatory variables
Male *	Binary variable: 1 = Male and 0 = Female
Age *	Continuous variable: Respondent’s age
Married	Binary variable: 1 = Currently married and 0 = Otherwise
Children *	Binary variable: 1 = Have child/children and 0 = Otherwise
Live alone	Binary variable: 1 = Living alone and 0 = Otherwise
Living in rural area	Binary variable: 1 = Living in rural areas (not Tokyo special wards or government designated city areas) and 0 = Otherwise
Education *	Continuous variable: Years of education
Employed	Binary variable: 1 = Respondent is employed and 0 = otherwise
Household income	Continuous variable: Annual earned income before taxes and with bonuses of the entire household in 2020 (unit: JPY)
Log of household income	Log of household income
Household assets	Continuous variable: Balance of financial assets (savings, stocks, bonds, insurance, etc.) of the entire household (unit: JPY)
Log of household assets	Log of household assets
Financial literacy *	Continuous variable: Average correct answers to three financial literacy questions
Subjective health status	Ordinal variable: 1 = It does not hold true at all for you; 2 = It is not so true for you; 3 = Neither true nor not true; 4 = It is rather true for you; 5 = It is particularly true for you, for the statement, “I am now healthy and was generally healthy in the last one year.”
Future anxiety	Ordinal variable: 1 = It does not hold true at all for you; 2 = It is not so true for you; 3 = Neither true nor not true; 4 = It is rather true for you; 5 = It is particularly true for you, for the statement, “I have anxieties about my life after I am 65 years old (for those who are already aged 65 or above, ‘life in the future’).”
Financial satisfaction	Ordinal variable: 1 = Completely disagree; 2 = Disagree; 3 = Neither agree nor disagree; 4 = Agree; 5 = Completely agree, for the statement, “Since the future is uncertain, it is a waste to think about it.” I am happy with my financial status.”
Feeling of depression	Ordinal variable: 1 = It does not hold true at all for you; 2 = It is not so true for you; 3 = Neither true nor not true; 4 = It is rather true for you; 5 = It is particularly true for you, for the statement, “I often feel depressed or felt depressed in the last one year.”
Myopic view of the future	Ordinal variable: 1 = Completely disagree; 2 = Disagree; 3 = Neither agree nor disagree; 4 = Agree; 5 = Completely agree, for the statement, “Since the future is uncertain, it is a waste to think about it.”

Note: * indicates data from the 2020 wave.