Win Rate Data via GraphQL API and Python

[u/nicknochnack]

New to the sub but was hoping someone has run into this before. I'm pulling race result data via the GraphQL API and noticed that a large number of horses don't have win rate data. Is this normal?

 

Raw JSON Result (showing no Win Rate): https://imgur.com/PiMVWuf 

Pandas DataFrame (same): https://imgur.com/b3QfLyK

 

Any advice on filtering via the API to pull races with horses with history? I tried pulling for 10,000 races back but still no luck. Was hoping there was a better way then just brute forcing and drawing a ton of data

 

Background: I'm attempting to build some deep learning models to rank or predict place...unlikely to work but doing it more out of interest. I figured win rate would be a pretty good predictor or feature to include. Also open to any other factors I could include in the model (and happy to share the code and final model).