It might be during a mid-morning break, or while she’s eating dinner late at night. Whenever she has a bit of spare time, Resha Patel opens her laptop and looks at her life and financial planning spreadsheet.

Budgeting for the family’s expenses across 46 categories, from the mortgage and groceries to children’s activities and clothing, Patel and her husband make a record of each day’s purchases in the YNAB (You Need a Budget) app to track their spending. In Excel, she has forecast expenditure for the next 17 years, to 2042 – the year her youngest child will finish high school.