Two market snapshots can look different simply because they cover different delivery periods. This comparison keeps the periods aligned and shows the movement between your earlier and later observations. It is a way to inspect a curve you already hold, including negative or zero prices, without presenting an equal-weight average as the price a business would pay for its own consumption.
Forward-curve movement comparison
Compare two dated sets of prices for the same delivery periods.
Compare the same market, unit, contract and delivery period. An equal-weight average is shown; it is not a volume-weighted procurement price.
What the result shows
Each delivery period is compared with the same named period in the other observation. The output shows the earlier price, later price, absolute movement and percentage movement where the earlier price is positive. It also shows an equal-weight average change across the entered periods. That average gives each period the same importance and should not be described as a weighted price for a particular supply portfolio.
Prepare the information for this review
The labels in the tool describe the measurement or record needed for each input. The following checks help keep the entered information consistent with the case you intend to review.
- Earlier observation date: Use the date supported by the underlying record. Check the day, month and year before running the tool, especially where an imported document uses a different date format.
- Later observation date: Use the date supported by the underlying record. Check the day, month and year before running the tool, especially where an imported document uses a different date format.
- Price unit, including currency: Use a clear name, reference or description that can be matched to your records. Expand abbreviations where the person receiving the result may not know how your business uses them.
Use the example CSV available in the tool to check the structure before preparing a larger file. Keep its header row, use one record per row and use plain numbers without currency symbols or thousands separators. Dates should follow the stated format. Quoted values can contain commas, but every row must have the same number of columns as the header.
- period: Use a consistent delivery or billing period label and compare it only with the matching period.
- old_price: Enter the earlier observation in the same market and unit as the later observation for this delivery period.
- new_price: Enter the later observation on a basis comparable with the earlier price, keeping source records alongside it.
The file is read in the browser when you select it or paste its contents. Check a small set of records first and compare the output with a manual example. Up to 20,000 data rows and 2 MB are supported. The result table displays records in pages where needed, while downloads include the full result rather than only the rows visible on screen.
Check the result against the source records
Compare the same market, unit, contract and delivery period. An equal-weight average is shown; it is not a volume-weighted procurement price.
Start with one case whose inputs you can trace back to the original records. Run the tool and compare its labels, units and dates with that example before preparing a wider review. If a value is uncertain, record the uncertainty in your working notes and resolve it with the person who holds the source information. A neatly presented result is useful only when the assumptions behind it are also clear.
Keep a copy and agree the next action
Use Download report to keep the written result and Download results CSV when you want to work with its records in a spreadsheet. Save inputs keeps a JSON file that can be restored into this same tool later. Editing an input hides the old result until you run the tool again, which helps avoid sharing an output that belongs to an earlier set of assumptions.
Where report emailing has been configured, Email my results lets you request a copy and send the same inputs and result to this site for follow-up about your request. The form explains who receives the copy and requires a completed security check. Check the recipient address carefully before sending. The email request uses the current result, so review the entered information before choosing that option.
For help with the next step, Explore specialist support.