> [!CAUTION]
> **Caution:** This documentation is for Google Ads API **v24** . The latest active version is [**v26**](https://developers.google.com/google-ads/api/reference/rpc/latest/SimulationTypeEnum.SimulationType).

Enum describing the field a simulation modifies.

[Proto definition ![GitHub](https://developers.google.com/site-assets/logo-github.svg)](https://github.com/googleapis/googleapis/blob/master/google/ads/googleads/v24/enums/simulation_type.proto)

| Enums ||
|---|---|
| ## `BID_MODIFIER` | The simulation is for a bid modifier. |
| ## `BUDGET` | The simulation is for a budget. |
| ## `CPC_BID` | The simulation is for a CPC bid. |
| ## `CPV_BID` | The simulation is for a CPV bid. |
| ## `PERCENT_CPC_BID` | The simulation is for a percent CPC bid. |
| ## `TARGET_CPA` | The simulation is for a CPA target. |
| ## `TARGET_IMPRESSION_SHARE` | The simulation is for an impression share target. |
| ## `TARGET_ROAS` | The simulation is for a ROAS target. |
| ## `UNKNOWN` | Used for return value only. Represents value unknown in this version. |
| ## `UNSPECIFIED` | Not specified. |