How to track net worth in a spreadsheet, and when to stop

A net worth spreadsheet is the simplest tracker there is: one row per month, one column per account, and a total. Assets are entered as positive numbers, debts as negative ones, every balance is read on the same day each month, and the total column is the net worth reading. Once the columns exist it takes ten minutes a month, and it produces the one thing that matters, a line of totals that can be compared. It stops being worth the ten minutes when the accounts multiply past a dozen, when the investment balances change too often to type, or when the household wants to read the figure more than once a month, and at that point an automatic tracker does the same job for less attention.

Why a spreadsheet works

Net worth is a sum, and a spreadsheet sums. The discipline the sheet imposes, one reading per month on a fixed day, is the discipline the measure needs, because a net worth read on random days measures the market's mood rather than the household's progress. And the sheet keeps history by default: the row from a year ago is still there, which is the comparison every judgment of the figure depends on.

Build it

1. One column per account, named as the bank names it, grouped with the assets on the left and the debts on the right. Include the manual ones: the house at its estimate, the car at resale, the cash on hand.
2. One row per month, dated the day the balances are read, the same day every month.
3. Assets positive, debts negative, so the total is a plain sum of the row.
4. A total column, and beside it a change-since-last-month column and a change-since-a-year-ago column.
5. A notes column for the events that explain a row: a car bought, a bonus received, a balance that could not be read that month.

A worked excerpt, three months

Three rows already show the two things a sheet is for: the total rising by the savings and the principal each month, and a month in which the market took back part of it. The home column does not move, because the estimate is updated once a year; the loan columns move every month by the principal paid.

Read it, monthly and yearly

Monthly, read the change column and the note. A change that matches the month's savings plus the principal paid is a normal month; a larger or smaller one has a cause, and the note says what. Yearly, read the total against the row twelve months up, and compute the ratios that judge the figure; see How to judge your net worth without comparing it to averages. The sheet's value is entirely in those two readings, and a sheet that is filled in but never read down the column is a chore without a return.

When to stop

The spreadsheet is the right tool as long as the ten minutes stay ten minutes and the monthly reading is enough. Three things end that.

• The accounts multiply. Past a dozen columns, the monthly read is a tour of a dozen logins, and a balance gets skipped, which is the stale row that misleads.
• The investment balances change daily, and typing a number that was wrong by the afternoon starts to feel pointless, which is when the monthly row stops being filled.
• The household wants the figure more often, before a purchase or a decision, and a sheet that is a month old cannot give it.

At that point an automatic tracker reads the connected accounts daily, takes the manual balances you set for the rest, and draws the line the sheet was building, and the ten minutes go to reading it rather than filling it. The sheet's history is worth keeping; its first rows are the earliest points on the line.

Common mistakes

• Reading balances on different days. The row mixes a payday balance with a pre-payday one, and the total swings for no reason.
• Entering the house at the purchase price and never updating. The column is fiction after the first year.
• Netting the mortgage into the home column. The mortgage is the part that changes monthly, and it deserves its own column.
• Skipping a month. The change column loses its meaning, and the habit loses its rhythm.
• Leaving out the notes. A dip with no note is a mystery a year later.
• Keeping the sheet after it has become a chore. A tracker that is not filled is a tracker that lies.

Common questions

How do I make a net worth spreadsheet? One column per account, assets positive and debts negative, one row per month read on the same day, a total column, a change column, and a notes column. Enter the house at its estimated sale price, the car at resale, and the loans at their remaining balances.

How often should I update it? Once a month, on a fixed day. Daily updates measure market noise, and quarterly ones lose the rhythm that keeps the habit.

Should I include my house and car? Yes, at what they would sell for today, with their loans as separate negative columns. See What counts as an asset and a liability for what goes in and at what value.

What if I miss a month? Fill the row from the statements, which show month-end balances, and note that it was reconstructed. The change column is worth more than a gap.

When should I switch to an app? When the number of accounts or the daily movement of the investment balances makes the monthly row a chore, or when you want the figure between readings. Keep the sheet's rows as history; they are the start of the line.

How Zypper handles this

Zypper is the sheet that fills itself. Connected accounts, checking, savings, cards, investment and retirement accounts, and loans, update automatically every day, and manual accounts for the house, the car, and anything else contribute whatever balance you set, so the row is read rather than typed; net worth is computed from all of them and charted over time, which is the total column as a line with every day on it rather than one day a month. The connections settings show each institution's status and when it last updated, so a stale balance is visible instead of silently wrong, and an expired connection is flagged and emailed about. See Net worth tracking, Manual accounts, and Checking connection status and refreshing for the details, or get started with Zypper to retire the spreadsheet and keep its history.