The average American 65 years of age and up earns an annual pre-tax income of $55,335, and that same group spends $52,141 yearly, or $4,345 a month, according to the Bureau of Labor Statistics (BLS).

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That income doesn’t leave a lot of extra cash for unexpected expenses or emergencies. The average American aged 65-69 has about $200,000 in retirement savings, according to an analysis of Federal Reserve data, and might still need to work even when they reach retirement age. High expenses often play a role.

Watch out for these four categories of spending that tend to take the biggest bite out of your monthly expenses.

1. Housing

Home costs represent the largest expense for retirees, accounting for 36% of their annual expenses, BLS figures show. Retirees who want to gain a leg up may want to consider downsizing as house prices remain high.

That could mean selling your current home for a profit – which leaves room to stash away money for retirement, boost your emergency fund or pay off debt. One drawback might be that you’ll also pay a high price for a replacement home in this market. But consider smart options such as relocating to a less expensive market or seeking out cooperative living situations with other retired couples.

2. Transportation

If you aren’t working as much or even at all, you might want to swap the car for public transit or a bicycle. Transportation is the second-largest spending category, making up $7,160 in annual expenses for retirees, according to BLS figures.

If your partner has a car, consider getting rid of one vehicle to cut costs. Even if you own your auto outright, car insurance, maintenance and repair costs for two cars add up.

Households can save almost $10,000 a year by taking public transportation and living with one less car, according to the American Public Transportation Association. You may also want to consider buying a powered scooter or motorized bike.

Read more: Worried you haven’t saved enough for retirement? Here’s how to get your savings on track

3. Health care

Health spending makes up $7,030 in annual spending for retirees. One way to cut costs when health issues arise is to get easily affordable preventative care. That means staying up to date on screenings and vaccinations. Exercise also appears in study after study as a top measure to lower the risk of many diseases. Even an activity as easy as walking can be beneficial.