# How i can record no change by INTERVAL_EVENT element?

**Category:** [Specifications](https://discourse.openehr.org/c/specifications/6)
**Created:** 2023-10-11 12:50 UTC
**Views:** 459
**Replies:** 0
**URL:** https://discourse.openehr.org/t/how-i-can-record-no-change-by-interval-event-element/4530

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## Post #1 by @Ivan_Ivanov

Good afternoon, dear colleagues.  In data structures information model https://specifications.openehr.org/releases/RM/latest/data_structures.html (6.1.5 Change Data) i see examples how i can record increase\decrease or change of variable, but how I can record no change in variable?
In my opinion i can it only by math_function **actual**. But maybe there are other ways.
P.S. In ADL i can record 0 in field with increase/decrease math_function, but i dont know is it bug. (see Pic.
![photo1696322381|358x284](upload://nPSsEuQzmzA5AGldSvTSraJo7tQ.jpeg)
)

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**Canonical:** https://discourse.openehr.org/t/how-i-can-record-no-change-by-interval-event-element/4530
**Original content:** https://discourse.openehr.org/t/how-i-can-record-no-change-by-interval-event-element/4530