> For the complete documentation index, see [llms.txt](https://docs.rigoblock.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.rigoblock.com/solidity-api-reference/protocol/types/observation.md).

# Observation

## Observation

```solidity
struct Observation {
  uint32 blockTimestamp;
  int24 prevTick;
  int48 tickCumulative;
  uint144 secondsPerLiquidityCumulativeX128;
  bool initialized;
}
```

## ObservationState

```solidity
struct ObservationState {
  uint16 index;
  uint16 cardinality;
  uint16 cardinalityNext;
}
```