Simplify CPI Price Tracking with Coda
Update prices to match inflation
It’s been a year since I unveiled the secret of the mirror effect in NPV calculations using Coda. In this blog we focus on CPI and you will learn that the Power() function can be replaced by something else.
To maintain price accuracy, consider adjusting your product prices annually in alignment with the Consumer Price Index (CPI). A practical way to implement this is by adding a new row to your product database each year, including a timestamp. This timestamp can then be used to filter and retrieve the appropriate price for any given time period. You can find a more detailed explanation of this method in this blog.
In this post, I’ll share a quick method for updating prices to reflect current market conditions and correct for past years, especially if you’ve missed a few annual adjustments. This simple process can help ensure your prices remain accurate and competitive.
The Consumer Price Index (CPI) is a key economic indicator that measures inflation. Our interactive tool allows you to see how the CPI has evolved over time. Use the slider to adjust the year, starting with the last year (2023), and view the corresponding CPI values. Moving the slider back by a specific number of years will reveal the CPI values for that period. For example, sliding back 4 years will show values for 2020–2023.
The next step is to get the percentages linked to each year.
While the Power() function is often handy for interest calculations, it assumes a constant interest rate over time. In our case, the CPI fluctuates yearly, requiring a different approach. Let’s explore a more versatile method that builds upon the core concept of the Power() function.
The screenshot demonstrates a calculation where each CPI value is incremented by one, and then all the resulting values are multiplied together using the Product()function.
Product() functionSince multiplication is commutative, the order of the values doesn’t affect the final result. The calculated adjustment factor is then added to the original product price, providing a dynamic pricing solution based on CPI fluctuations.
I hope this article was informative and helpful. Did it help you to solve a problem you unlike would have solved other ways? What about a donation?
My name is Christiaan, and I regularly blog about Coda. While this article is free, my professional services (including consultations) are not, but I’m always happy to chat and explore potential solutions. You can find my free contributions in the Coda Community and on X. The Coda Community is a fantastic resource for free insights, especially when you share a sample doc.
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