Why am I seeing fractional conversions?

An overview of Google SEM conversions

For Google (Search Engine Marketing, Display, and YouTube) Reporting, you may see decimals on your conversions. This is due to position-based attribution modeling for conversions.

Most advertisers measure the success of their online advertising on a "last click" basis. This means they give all the credit for a conversion to the last clicked ad and corresponding keyword. However, this ignores the other ad interactions customers may have had along the way.

Google Ads offers several attribution models that give more fair credit to all the touchpoints in the customer journey.

For instance, the Position-Based conversion attribution model gives a 40% attribution to the first and last click each and 20% to anything in between.

Learn more about the different attribution models Google offers via this link.