In the Calendar, add challenges or accomplishments like "# of no-spend days per month", "# of days spent is below X amount", "# of days without spending on takeout".
Can show a streak for consecutive days of no spend or could have badges that can be earned and displayed next to each week in the calendar, eg:
  • "My own chef": For weeks with no "Restaurant" or "Take out" spending
  • "Coffee is for the weak": For weeks with no spending in "Coffee Shops"
  • "Big saver": For weeks where there is a transfer transaction to "Savings" or "Investments"