# Personal Inflation Rate: Measure Yours From Statements

- Author: CheapBankConvert (https://cheapbankconvert.com)
- Published: 2026-10-17
- Category: Cutting costs from your statements
- Canonical: https://cheapbankconvert.com/blog/personal-inflation-rate

> Measure your personal inflation rate by comparing the same spending categories across two years of statements, and see what drove it.
Your personal inflation rate is how much more you paid this year than last year for the same kinds of spending, as a percentage. To measure it, total the same categories from two years of bank statements, divide the increase by last year's total, and look at which category moved the most. That category is what drove your number.

## What is a personal inflation rate, and how does it differ from the CPI?

A personal inflation rate is the change in your own household's costs from one year to the next, worked out from what you actually pay. The Consumer Price Index, or CPI, is a national average built from a fixed basket of goods and services. The two can differ widely, because your basket is not the average one.

The Bureau of Labor Statistics, which publishes the CPI, says so directly in its [CPI questions and answers](https://www.bls.gov/cpi/questions-and-answers.htm): a national average reflects millions of individual price experiences and seldom mirrors a particular consumer's experience. The same page notes that the main index covers urban households, which make up over 90 percent of the US population, so it leaves some groups out.

Why your number may be higher or lower than the headline:

- **Housing.** Rent or a mortgage is the largest cost for most households. A renter whose lease jumped feels inflation very differently from an owner with a fixed-rate mortgage.
- **Driving.** If you drive a lot, fuel and car insurance weigh more in your basket than in the average one.
- **Diet and household size.** A large family spends a bigger share on groceries.
- **Where you live.** Local rents, utility rates and insurance premiums vary by region.

The national figure is still useful as a yardstick. If your rate is well above it, one or two categories are usually responsible, and those are the ones worth attention.

## Choosing statement categories for a personal inflation rate

The categories for a personal inflation rate should be recurring costs you buy in roughly the same amount each year, so that a change in spending mostly reflects a change in price. Rent, insurance, utilities, phone and internet, groceries, fuel, subscriptions and eating out are the usual set. One-off purchases do not belong.

Start by gathering twenty-four months of statements, from every account that pays household costs. Many banks keep that much history online. For one bank's steps, see [downloading TD Bank statements](/blog/download-td-bank-statements). Credit card statements count too, if groceries or fuel go on a card.

Then sort each row into a category. A few rules keep the comparison fair:

- **Use the same months.** Compare January to December with January to December, or any matching twelve months.
- **Keep the same category rules in both years.** If takeaway counts as eating out in one year, it must in the other.
- **Leave out transfers** between your own accounts and credit card payments, which would count spending twice.
- **Leave out large one-offs** such as a new sofa, a car repair or a holiday. They change spending but tell you nothing about prices.
- **Watch for fees.** A bank fee that appears once, such as a wire for a house deposit, is a one-off. [What wire transfer fees cost](/blog/wire-transfer-fees) covers those charges, but they belong outside the comparison.

Getting two years of statements into one spreadsheet is most of the work. Once [CheapBankConvert](/) opens, it will convert each PDF statement into CSV or Excel for a single payment, so you can paste every month into one sheet and categorize it once.

## How do you calculate a personal inflation rate from two years of statements?

To calculate a personal inflation rate, add up last year's total for your chosen categories and this year's total for the same categories. Subtract last year from this year, then divide by last year. The answer, as a percentage, is your rate. Each category's own change shows where it came from.

With last year's category totals in column B and this year's in column C, starting in row 2:

- **Category change, column D:** `=(C2-B2)/B2`, formatted as a percentage.
- **Contribution in percentage points, column E:** `=(C2-B2)/SUM(B:B)`, formatted as a percentage. This shows how much of the overall rate each category produced.
- **Overall rate:** `=(SUM(C:C)-SUM(B:B))/SUM(B:B)`.

The contributions in column E add up to the overall rate. That is the useful part. A category with a big percentage change may contribute little if you spend little on it, while a small change in rent can dominate the result.

Some people prefer to weight each category by last year's share of spending and average the category changes. That gives the same answer as the overall formula above, because the weights are built into the totals.

## A worked personal inflation rate across eight spending categories

A worked example makes the drivers easy to see. The table below uses made-up totals for a household over two calendar years. The overall rate is 4.65%, and rent alone produced more than half of it, even though car insurance had the largest percentage rise.

| Category (example) | Last year | This year | Change | Contribution |
| --- | --- | --- | --- | --- |
| Rent | $18,000 | $18,900 | +5.0% | +2.51 points |
| Groceries | $7,200 | $7,560 | +5.0% | +1.00 points |
| Utilities | $2,400 | $2,568 | +7.0% | +0.47 points |
| Car insurance | $1,500 | $1,710 | +14.0% | +0.58 points |
| Fuel | $2,000 | $1,900 | −5.0% | −0.28 points |
| Phone and internet | $1,800 | $1,872 | +4.0% | +0.20 points |
| Eating out | $2,400 | $2,400 | 0.0% | 0.00 points |
| Subscriptions | $600 | $660 | +10.0% | +0.17 points |
| **Total** | **$35,900** | **$37,570** | **+4.65%** | **+4.65 points** |

The contributions add to 4.65 points within rounding. Reading the table:

- **Rent drove the result.** A 5% rise on the biggest cost produced 2.51 of the 4.65 points.
- **Car insurance rose the most in percentage terms**, 14%, but added only 0.58 points because it is a smaller line.
- **Fuel fell**, which pulled the rate down a little.
- **Eating out stayed flat.** That might mean prices held, or that the household ate out less often at higher prices. The statement cannot tell you which.

If this household compared its 4.65% with the CPI for the same period, the gap would point straight at rent and insurance as the reasons.

## When a spending change is not personal inflation

A spending change is not personal inflation when you bought more or less of something, rather than paying a different price for the same thing. Statements show what you spent, not what each item cost, so a category can rise because your habits changed. Take those changes out, or note them, before you trust the rate.

Changes that look like inflation but are not:

- **A new household member or a pet.** Groceries rise because there are more mouths, not because prices did.
- **A move.** A new home changes rent, utilities and commuting all at once. Compare only the months after the move, or treat it as a new baseline.
- **A new service or a dropped one.** Adding a streaming plan raises subscriptions, cancelling one lowers them. Neither is a price change.
- **A switch of provider.** Moving to a cheaper phone plan lowers spending even if prices in general rose.
- **Timing quirks.** An annual insurance premium paid in December one year and January the next can put two payments in one year and none in the other.

A good check for groceries is a few receipts. Pick five items you buy every week and compare their prices with last year's receipts or online orders. If the items cost about 5% more and grocery spending rose 5%, the rise is price. If the items cost 2% more and spending rose 5%, you bought more.

The cleaner your categories, the more the rate tells you. It is better to drop a messy category from the comparison than to let it distort the result.

## Planning next year's budget with your personal inflation rate

Your personal inflation rate is a planning number. Use it to raise next year's budget for the categories that keep rising, to check whether your income kept pace, and to pick the costs worth fighting. A category that drove your rate is the first place to look for a cheaper quote or a change of habit.

Practical uses:

- **Set next year's budget lines.** Add each category's own change, not the overall rate, to this year's totals. Rent may follow your lease, while subscriptions follow price announcements.
- **Compare with your pay rise.** If take-home pay rose 3% and your rate was 4.65%, you are worse off by the difference, and the budget needs to absorb it somewhere.
- **Target the drivers.** In the example, shopping around for car insurance attacks a 14% rise directly. Ideas for the other lines are in [how to cut monthly expenses](/blog/how-to-cut-monthly-expenses).
- **Repeat it every year.** Keep the sheet and add a new column each January. Three years of numbers show whether a category is a steady climber or a one-year jump.

The rate is only as good as the rows behind it, so keep the categories, the months and the one-off rules the same each time you run it. A change of method between years shows up as a fake rise or fall, and it hides the price changes you set out to measure.