---
title: Last observation carried forward | Tiger Data Docs
description: Fill gaps in your data by carrying the last observation forward
---

**LOCF** (last observation carried forward) fills gaps by repeating the last known value until the next sample arrives. Use it when a stepped or held reading matches your signal better than drawing a straight line between points.

For more information about gapfilling and interpolation API calls, see the [hyperfunction API documentation](/docs/reference/timescaledb/hyperfunctions/time_bucket_gapfill/locf/index.md).