A data scientist who retired at 36 shares 3 charts that helped him manage his money and get out of the corporate world early

The chart above, which Goldstein checks every morning, shows his expenses for the first two months of 2024.

Goldstein divides his expenses into two broad categories: fixed and variable. He also has detailed sub-categories including food, family, entertainment, and guilty pleasures.

For each cost, he tracks details including his year-to-date spending, the percentage of his budget that it accounts for, and how much of his budget remains available.

The chart on the right shows a different visual breakdown of his expenses. The bigger the rectangle, the higher the expense. The expenses called "guilty pleasures" and "apartment" make up for big parts of his budget; "friends and social" and "education," both of which are smaller boxes, account for less of it.

Goldstein said he's closely tracking his spending on unhealthy foods because he is prioritizing fitness and working to lower his "stress eating" after retirement.

"My apartment rent is one of my largest cost categories, together with how much money I spend on food in general," he told BI.

The chart above tracks how Goldstein's total net worth has changed since he retired in May. The Y-axis value, which has been concealed here at Goldstein's request, tracks Goldstein's net worth.

"It's ok for it to go down as long as it goes up again," Goldstein said. "I'm very lucky that it went up so much in the first months, because I originally retired with only 'guaranteed' $3,500 per month, but now I'm more safely in the $4,500-$5,000 range," he said about his monthly budget.

His cost of living is roughly 60% of that amount. He said 20% of his monthly "salary" goes into travel, and gifts for family and friends. He keeps the remaining 20% invested in stocks.

As a single person living in Berlin, Goldstein feels comfortable living off 80% of his budget and keeping the rest invested. However, he said his priorities could change if he settles with a partner and has children.

Goldstein's portfolio breakdown is another treemap chart with stock ticker names for various companies.

"My largest holding is Berkshire Hathaway, managed by Warren Buffett, followed by Google," he said.

He built the tool in 2015 when he learned that Google Sheets allows users to get up-to-date information about stock prices directly. Since then, he said he has been using the sheet to track "daily snapshots" of his net worth over the years.

"It's a little bit my baby that grew with me over the last 10 years," he said.

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